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303 Cards in this Set
- Front
- Back
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What is the term for a single layered arrangement of epithelial cells?
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simple
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Which of the following epithelia is commonly used for filtration or osmotic exchange?
simple squamous, stratefied squamous, simple columnar, pseudostratefied columnar, transitional |
simple squamous
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Which of the following epithelia is primarily protective and subjected to surface wear and tear?
simple squamous simple cuboidal stratified squamous pseudostratefied transitional |
stratified squamous
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What type of gland is associated with a duct or body cavity?
exocrine endocrine hormonal pituitary thyroid |
exocrine
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Which of the following are unicellular glands that secrete mucus?
tubuloalveolar merocrine holocrine goblet endocrine |
goblet
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Simple, compound, tubular, alveolar, and tubuloalveolar all apply to:
endocrine glands exocrine glands secretion composition hormones |
exocrine glands
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Which of the following is NOT a connective tissue function?
establishes a structural framework transporting fluids and dissolved materials protecting delicate organs storing energy reserves conducting electrochemical impulses |
conducting electrochemical impulses
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The online tissue lab places connective tissues into which category(ies)?
a) connective tissue proper b) fluid connective tissue c) supporting connective tissue d) a, b, and c are all connective tissue categories |
d) a, b, and c are all connective tissue categories
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They are the most abundant cells in this tissue. They secrete materials that compose the ground substance and extracellular fibers.
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fibroblasts
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Which of the following is NOT a type of connective tissue fiber?
dendrite collagen reticular elastic |
dendrite
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Identify this connective tissue that provides padding, insulates, and absorbs shock.
reticular fluid adipose simple squamous striated |
adipose
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Which of the following fibers stabilizes cells, organs, and blood vessels?
adipose reticular fluid cartilage stratified cuboidal |
reticular
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The tissue from the stomach wall is?
striated muscle smooth muscle cardiac muscle fluid connective adipose |
smooth muscle
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Which of these are a involuntary tissue?
striated muscle smooth muscle cardiac muscle nerve |
cardiac muscle
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Which of these is a voluntary tissue?
striated muscle smooth muscle areolar connective cardiac muscle |
striated muscle
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Which of these are electrochemically conductive cells?
simple squamous adipose smooth muscle nerve cells reticular connective |
nerve cells
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The multiple "incoming" branches on cells are?
axons cell bodies dendrites reticular columnar |
dendrites
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The singular "outgoing" branches on cells are:
axons dendrites cell bodies squamous cuboidal |
axons
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A monohybrid cross is
the second generation of a self-fertilized plant. a breeding experiment in which the parental varieties have only one trait in common. a breeding experiment in which the parental varieties differ in only one trait. a triploid plant that results from breeding two very different plants. None of the choices are correct. |
a breeding experiment in which the parental varieties differ in only one trait.
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Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's firstborn child is female and second-born child is male?
25% 50% 75% 100% None of the choices are correct. |
25%
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A carrier of a genetic disorder who does not show symptoms is most likely to be __________ to transmit it to offspring.
heterozygous for the trait and able heterozygous for the trait and unable homozygous for the trait and able homozygous for the trait and unable None of the choices are correct. |
heterozygous for the trait and able
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Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form of deafness. Deafness is a recessive trait that is associated with the abnormal allele d. The normal allele at this locus, associated with normal hearing, is D. Dr. Smith's parents could have which of the following genotypes?
DD and dd dd and dd Dd and Dd DD and DD None of the choices are correct. |
Dd and Dd
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Imagine that beak color in a finch species is controlled by a single gene. You mate a finch homozygous for orange (pigmented) beak with a finch homozygous for ivory (unpigmented) beak and get numerous offspring, all of which have a pale, ivory-orange beak. This pattern of color expression is most likely to be an example of
incomplete dominance. co-dominance. pleiotropy. polygenic inheritance. crossing over. |
incomplete dominance
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The expression of both alleles for a trait in a heterozygous individual illustrates
incomplete dominance. co-dominance. pleiotropy. polygenic inheritance. blending inheritance. |
co-dominance
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Which of the following terms refers to the situation where a single phenotypic characteristic is determined by the additive effects of two or more genes?
incomplete dominance. co-dominance. pleiotropy. polygenic inheritance. blending inheritance. |
polygenic inheritance
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Linked genes generally
follow the laws of independent assortment. do not follow the laws of independent assortment. show incomplete dominance. reflect a pattern of co-dominance. show pleiotropy. |
do not follow the laws of independent assortment
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What is the normal complement of sex chromosomes in a human male?
two X chromosomes two Y chromosomes two X chromosomes and one Y chromosome one X chromosome and one Y chromosome one Y chromosome |
one X chromosome and one Y chromosome
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Recessive X-linked traits are more likely to be expressed in a male than a female because
males are haploid. the male's SRY gene doubles the chances that sex-linked genes are expressed. the male's phenotype results entirely from his single X-linked gene. More than one of the choices is correct. None of the choices are correct. |
the male's phenotype results entirely from his single X-linked gene
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A karyotype is most like which of the following?
A map showing the hidden location of buried treasure A movie showing the stages of the reproductive cycle of a beetle A necklace formed by stringing beads onto a string Photographs of every couple at a high school prom The answer key to a multiple choice exam |
Photographs of every couple at a high school prom
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Nondisjunction occurs when
a portion of a chromosome breaks off and is lost. chromosomes replicate too many times. two chromosomes fuse into one. members of a chromosome pair fail to separate. an entire pair of chromosomes is lost during meiosis I. |
members of a chromosome pair fail to separate
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Solve this monohybrid genetics problem: Black hair is governed by the dominant gene (B) and blond hair is determined by the recessive gene (b). In this monohybrid cross, if both parents are heterozygous, what percentage of the offspring would be expected to have blond hair
75% 50% 100% 25% 33.3% |
25%
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Which of the following is the BEST description of Mendel's principle of independent assortment?
There is always one allele that is dominant over another Genes for different characteristics sort into eggs or sperm without regard for the position of other genes on other chromosomes. Genes from each parent are blended together in the offspring, resulting in the offspring having a mixture of characteristics from both Each offspring will receive a gene from the female parent and a gene from the male parent Males and females mate with each other based on predetermined sexual stimuli. In other words, mating is not completely independent of all factors. |
Genes for different characteristics sort into eggs or sperm without regard for the position of other genes on other chromosomes
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If both parents in a dihybrid cross are heterozygous for both traits, the expected phenotypic ratio in the offspring would be
1:1 2:1 9:3:3:1 1:2:1 The results vary from individual to individual. |
9:3:3:1
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Solve the following multiple allele problem: Susan, a mother with Type B blood, has a child with Type O blood. She claims that Craig, who has Type A blood, is the father. He claims that he cannot possibly be the father. Further blood tests ordered by the judge reveal that Craig is AA. The judge rules that
Susan is right and Craig must pay child support. Craig is right and doesn't have to pay child support. Susan cannot be the real mother of the child; there must have been an error made at the hospital. It is impossible to reach a decision based on the limited data available. |
Craig is right and doesn't have to pay child support
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Different alleles of the same gene are found
at the same place on mitochondrial chromosomes. at different places on homologous chromosomes. at the same place on homologous chromosomes. throughout the chromosomes at different places. in different individuals on different chromosomes. |
at the same place on homologous chromosomes
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If you had an individual who showed a dominant phenotype and you wanted to find out if the individual was homozygous or heterozygous, you could do a test cross. You would cross the unknown with a known
homozygous dominant. heterozygous. homozogous dominant or heterozygous individual. individual that looks just like itself. homozygous recessive. |
homozygous recessive
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Many genetic disorders of humans are caused by
multiple alleles. recessive alleles. drinking during pregnancy. a mutation that occurs in the egg, sperm, or zygote that gives rise to the affected individual. interactions with others who have the disease. |
recessive alleles
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Which of the following is FALSE?
Genetic testing before birth requires the collection of fetal cells. Carrier testing helps determine if a person carries a potentially harmful disorder. Most children with recessive disorders are born to healthy parents. Newborn screening can catch inherited disorders right after birth. Most human genetic diseases are treatable if caught early. |
Most human genetic diseases are treatable if caught early.
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A person who has type AB blood illustrates the principle of
co-dominance. incomplete dominance. blending inheritance. polygenic inheritance. regressive absorption. |
co-dominance
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Sometimes, linked genes are not inherited because they are broken apart during the formation of the gametes. These breaks are caused by
co-dominance. random probability. crossing over. incomplete mitosis. linkage reversal. |
crossing over
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How many sex chromosomes are in an egg or a sperm?
one two 23 46 It varies from individual to individual. |
one
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By studying a karyotype, a prospective parent would be able to tell
if there is a mutation of a specific gene on a specific chromosome. if there is an alteration in the number of chromosomes. if the child is likely to develop cancer sometime during his or her life. the eye color and hair color of the child. the sex of the next child conceived by this couple. |
if there is an alteration in the number of chromosomes.
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In the gene arrangement ABCDEFG breaks and a segment repositions itself so that the segment now reads ABEDCFG, what specific kind of mutation has occurred?
Deletion Translocation Inversion Nondisjunction Reciprocal mutation |
Inversion
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Which of the following genotypes would be homozygous dominant for both alleles?
Ddee DDEe ddee DDEE DdEe |
DDEE
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If a colorblind woman marries a colorblind man, the chances of any daughter being of normal vision is
0% 25% 50% less than 25% It is impossible to tell, as the grandparents' genotype have to be figured into the problem. |
0%
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When you trace the occurrence of a specific characteristic through your past ancestry, you are constructing a family ______________.
genetic probability chart incidence of occurrence genotype reference pedigree meiotic history |
pedigree
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Human skin color varies greatly from one individual to another. The specific genetic situation to account for this fact is
multiple alleles - there are many genes that govern the characteristic of skin color. pleiotropy - single genes govern a variety of characteristics like skin and hair color. polygenic inheritance - several genes act together to govern the phenotype of a certain characteristic. environmentalism - skin color is determined by the amount of sun exposure the child gets. co-dominance - several genes are expressed together and one is not dominant over the other. |
polygenic inheritance - several genes act together to govern the phenotype of a certain characteristic.
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Mendel was fortunate to work out the laws of segregation and independent assortment because he used an organism that reproduced quickly and in which the traits were discrete (easy to observe). Mendel's organism of choice was the
elephant. dog. other monks at the Abby. pea plant. common garden toad. |
pea plant
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The monomers of DNA and RNA are
amino acids. monosaccharides. nucleotides. fatty acids. nucleic acids |
nucleotides
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The copying mechanism of DNA is most like
using a photographic negative to make a positive image. mixing flour, sugar, and water to make bread dough. joining together links to make a chain. carving a figure out of wood. threading beads onto a string. |
using a photographic negative to make a positive image.
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When one DNA molecule is copied to make two DNA molecules, the new DNA contains
25% of the parent DNA. 50% of the parent DNA. 75% of the parent DNA. 100% of the parent DNA. none of the parent DNA |
50% of the parent DNA
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The one gene-one polypeptide theory states that
the synthesis of each gene is catalyzed by one specific enzyme. the synthesis of each enzyme is catalyzed by one specific gene. the function of an individual gene is to dictate the production of a specific polypeptide. each polypeptide catalyzes a specific reaction. None of the choices are correct |
the function of an individual gene is to dictate the production of a specific polypeptide
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The transfer of genetic information from DNA to RNA is called
translation. transcription. initiation. elongation. promotion. |
transcription
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Experiments have demonstrated that the words of the genetic code (the units that specify amino acids) are
single nucleotides. two-nucleotide sequences. three-nucleotide sequences. nucleotide sequences of various lengths. enzymes |
three-nucleotide sequences
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Which of the following enzymes catalyzes the linking of RNA nucleotides to form RNA?
RNA polymerase RNA ligase a ribozyme reverse transcriptase tRNA |
RNA polymerase
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Translation consists of which of the following?
-the conversion of genetic information from the language of nucleic acids to the language of proteins -the conversion of genetic information from DNA nucleotides into RNA nucleotides - the addition of nucleotides to a DNA template - the conversion of genetic information from the language of proteins to the language of enzymes - DNA replication |
the conversion of genetic information from the language of nucleic acids to the language of proteins
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A physical or chemical agent that changes the nucleotide sequence of DNA is called
a reverse transcriptase. a terminator. a transposon. a mutagen. an anticodon. |
a mutagen
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Replication of DNA is said to be semiconservative because
each separated strand serves as a template to make an exact copy. the whole DNA molecule serves as a template for making new DNA. DNA makes mRNA, which in turn codes for the formation of tRNA. fragments of each strand code for the formation of a new strand. politically liberal individuals are not successful at replicating their DNA. |
each separated strand serves as a template to make an exact copy
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Each DNA strand has a backbone that consists of alternating
purines and pyramidines. nitrogen-containing bases. hydrogen bonds. sugar and phosphate molecules. ribose and deoxyrobose sugars. |
sugar and phosphate molecules
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DNA polymerase
is an enzyme. adds new nucleotides to a strand. proofreads DNA strands to see that they are correct. derives energy from ATP for synthesis of DNA strands. All of the above are correct. |
All of the above are correct
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If the DNA triplets were ATG-CGT, the mRNA codons would be _____________.
AUG-CGU ATG-CGT UAC-GCA UAG-CGU None of the above are correct. |
UAC-GCA
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A chromosome that has been broken and rejoined in a reversed sequence has undergone which of the following mutations?
Translocation Deletion Inversion Duplication Doubleation |
Inversion
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Which of the following is the enzyme that HIV uses to synthesize DNA on an RNA template?
ligase RNA polymerase terminator enzyme reverse transcriptase None of the choices are correct. |
reverse transcriptase
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One type of virus that infects bacteria is called a(n)
phage. mage. rhinovirus. filovirus. Ebola |
phage
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Sticky Ends are
produced by the action of DNA ligase. produced by PCR. always long sequences of a single nucleotide. used by mRNA to attach to ribosomes. DNA fragments with single-stranded ends |
DNA fragments with single-stranded ends
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DNA ligase binds
exons together. polymerase to the promotor. nucleotides together. introns together. All of the choices are correct. |
nucleotides together
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In the process of human gene cloning using recombinant plasmids, the bacterial plasmid
functions as a vector. is the source of the gene to be cloned. is cultured inside the human cell, which contains the gene to be cloned. is used to insert the human gene into the bacterial chromosome. None of the choices are correct. |
functions as a vector
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Retroviruses such as HIV use __________ to convert information stored in their RNA to information stored in DNA.
DNA ligase reverse transcriptase a restriction enzyme a terminator enzyme RNA polymerase |
reverse transcriptase
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Genetically modifying __________ cells may directly affect future generations.
intestinal basal somatic germ somatic and germ |
germ
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If you commit a crime, you need to make sure that you do not leave even the smallest speck of blood, hair, etc., from your body behind, because if you do, the DNA in this material can be amplified by __________, subjected to genetic analysis, and used to identify you as the perpetrator of the crime.
ATP PCR blotting RFLP reverse transcriptase |
PCR
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Segments of eukaryotic DNA that can move or be copied from one site to another in the genome are called
exons. plasmids. transposons. introns. vectors. |
transposons
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Gel electrophoresis separates DNA molecules on the basis of
the nucleotide sequence of their sticky ends. their nucleotide sequences. the amount of adenine they contain relative to the amount of thymine they contain. the amount of adenine they contain relative to the amount of guanine they contain. their lengths |
their lengths
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When a virus takes over the machinery of a cell, it forces the cell to manufacture
more mitochondria for energy reactions within the virus. more liposomes to isolate themselves from dangerous water. more food molecules. more viral particles. more endoplasmic reticulum channels used to expel the viruses. |
more viral particles
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If one sticky end has the nucleotide sequence TTAA exposed, the piece of DNA that will come in and attach to that sticky end will have the sequence ___________.
TTAA UUAA GGCC CCGG AATT |
AATT
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A harmless variant or derivative of a pathogen that is used to prevent infectious disease is called a __________.
vaccine type variant inoculation phage change anti-pathogen |
vaccine
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In the gel electrophoresis chamber, the DNA fragments migrate toward the __________ charged pole.
positively negatively positively or negatively charged pole, depending on the charge of the fragment enzymatically radioactively |
positively
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A transgenic organism has acquired genes from
members of its own gene line that go back at least three generations. other members of its existing population. another species. a member of the opposite sex. only its own genes which have been cultured in the lab. |
another species
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Most scientists do not consider viruses to be alive because
they infect a host cell. they are unable to reproduce on their own. they have no genes. no definite structural features are seen under the microscope. All of these. |
they are unable to reproduce on their own
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The basic difference between Mendel's particulate theory of inheritance and the previous blending theory was that the blending theory, but not the particulate theory, maintained that _____.
mutation is the major source of new gene combinations many genes are lost in their transmission to offspring, but the remaining genes gradually reproduce the lost genes the traits governed by genes in the egg are different from the traits governed by genes in the sperm after a mating, genes of the two parents are mixed in the offspring and lose their individual identities genes combine with each other to produce new genes |
after a mating, genes of the two parents are mixed in the offspring and lose their individual identities
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The cross-fertilization of two different varieties of pea plants will produce a(n) _____.
F2 generation lethal hybrid P generation individual homozygous for many different genes |
hybrid
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In a certain plant, the alleles A, B, and C are dominant to the alleles a, b, and c. A plant with the genotype AABbcc will have the same phenotype as the plant with the genotype _____.
AAbbcc aabbcc AaBBcc AABBCc none of the above |
AaBBcc
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Cystic fibrosis can be inherited even if neither parent has the disease. This is because the disease _____.
requires certain environmental conditions to be expressed occurs only in polyploid individuals is caused by a recessive allele is caused by a dominant allele occurs only in individuals who are already weak from other causes |
is caused by a recessive allele
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Assume tall (T) is dominant to dwarf (t). If a homozygous dominant individual is crossed with a homozygous dwarf, the offspring will ______.
all be intermediate in height all be tall be 1/2 tall and 1/2 dwarf be 3/4 tall and 1/4 dwarf all be short |
all be tall
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Phenylketonuria is an autosomal recessive disorder. Using P and p to represent the alleles, what is the genotype of a phenylketonuric person?
PP Pp pp Pp or pp all of the above |
pp
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If a homozygous dominant is crossed with a homozygous recessive for a given trait, the offspring will be __________.
all of the dominant phenotype 1/4 of the recessive phenotype all homozygous dominant all homozygous recessive present in a 9:3:3:1 ratio |
all of the dominant phenotype
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In a cross between two heterozygotes (Aa), the next generation will be _____.
in the ratio 1:3 heterozygotes to homozygotes all heterozygotes in the ratio 1:1 homozygotes to heterozygotes all homozygotes in the ratio 1:3 homozygotes to heterozygotes |
in the ratio 1:1 homozygotes to heterozygotes
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In Mendel's monohybrid cross of purple-flowered and white-flowered peas, all members of the F1 generation were of the __________ phenotype because their genotype was __________ for the flower-color gene.
white-flowered ... homozygous recessive white-flowered ... heterozygous purple-flowered ... homozygous recessive purple-flowered ... homozygous dominant purple-flowered ... heterozygous |
purple-flowered ... heterozygous
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Huntington's disease is due to an autosomal dominant allele. If a heterozygous male marries a normal female, what percentage of the offspring will have Huntington's?
0% 25% 50% 75% 100% |
50%
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An allele is _____.
a type of chromosome the dominant form of a gene a variety of pea plant used by Mendel an alternative version of a gene the recessive form of a gene |
an alternative version of a gene
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Folk singer Woody Guthrie died of Huntington's disease, an autosomal dominant disease. Which statement below must be true?
All of his children will die of Huntington's disease. His sons will die of Huntington's disease but not his daughters. His daughters will die of Huntington's disease but not his sons. At least one of Woody Guthrie's parents must have had Huntington's disease also. There is not enough information to answer the question. |
At least one of Woody Guthrie's parents must have had Huntington's disease also
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Homologous pairs of chromosomes frequently _____.
carry different genes for different traits differ in length contain different alleles are not both present in diploid cells are paired up during interphase |
contain different alleles
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An AABb individual is mated with another AABb individual. The possible number of genetically different kinds of offspring is _____.
1 2 3 4 9 |
3
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Pea flowers may be purple (W) or white (w). Pea seeds may be round (R) or wrinkled (r). What proportion of the offspring from the cross WwRr x WwRr will have white flowers and wrinkled seeds?
0.0625 0.1875 0.5625 0.75 all of them |
0.0625
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A = big apples; R = red apples; a = small apples; r = yellow apples. You have one tree that produces big yellow apples and another tree that produces small red apples. When the two are crossed, you find that half the offspring trees produce big red apples and half produce big yellow apples. What are the genotypes of the parents?
AArr and aaRr Aarr and aaRr AARr and AArr AaRr and AaRr AaRr and aarr |
AArr and aaRr
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R = can roll tongue; r = can't roll tongue. A couple who both have the ability to roll their tongues have a son who is also a tongue-roller. The son is curious about whether he is homozygous or heterozygous for the tongue-rolling trait. How could he find out?
Have children with a woman who is also a tongue-roller. If their children are tongue-rollers, then he is a homozygous dominant. Have children with a woman who is also a tongue-roller. If all their children are non-rollers, then he is a heterozygote. Have children with a woman who is a non-roller. If any of their children is a non-roller, then he is a heterozygote. Have children with a woman who is a non-roller. If any of their children is a tongue-roller, then he is a homozygous recessive. He will have to wait to have grandchildren before the question can be answered. |
Have children with a woman who is a non-roller. If any of their children is a non-roller, then he is a heterozygote.
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Pea plants are tall if they have the genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant. Half the offspring are tall, and half are short. This allows us to conclude that the tall plant _____.
was homozygous was heterozygous had two tall parents all of the above none of the above |
was heterozygous
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The results of a testcross (that is, the offspring of this cross) were 50% phenotypically dominant and 50% phenotypically recessive. The genotype of the phenotypically dominant parent in this cross was _____.
homozygous dominant homozygous recessive heterozygous homozygous dominant and homozygous recessive the answer cannot be determined from the information |
heterozygous
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What is indicated when a single-character testcross yields offspring in a 1:1 phenotypic ratio?
The parent with the dominant phenotype was homozygous. The parent with the dominant phenotype was heterozygous. Epistasis has occurred. Alleles are codominant. Both parents are heterozygous. |
The parent with the dominant phenotype was heterozygous.
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Suppose we have a pea plant with purple flowers, determined by the dominant allele P. How might you determine whether the plant is homozygous (PP) or heterozygous (Pp)?
Perform a testcross: Cross the plant with a known heterozygote, Pp. Cross the plant with a true-breeding purple plant. Examine the plant's chromosomes with a microscope. Perform a testcross: Cross the plant with a white one, which must be homozygous recessive, or pp. Attempt to cross the plant with a pink-flowered snapdragon. |
Perform a testcross: Cross the plant with a white one, which must be homozygous recessive, or pp.
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If each parent can produce 100 genetically distinct gametes, how many genetically distinct offspring can two parents produce?
10,000 200 1,000 100 1,000,000 |
10,000
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Tay Sachs disease runs in Rebecca's family. On a family pedigree, she saw a shaded circle. This represented _____.
a male with Tay Sachs a female carrier a male carrier a female with Tay Sachs a male of unknown genotype |
a female with Tay Sachs
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John and Jane are planning a family, but since each has a brother who has sickle-cell disease, they are concerned that their children may develop sickle-cell disease. Neither John, Jane, nor their respective parents have the disease. They consult a genetic counselor who tells them that _____.
there is no chance that any of their children will have sickle-cell disease all of their children will have sickle-cell disease one of four of their children can be expected to have sickle-cell disease it's possible that none of their children will have the disease, but blood tests on them both will be required to make sure it is impossible to tell whether their children will have the disease |
it's possible that none of their children will have the disease, but blood tests on them both will be required to make sure
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When two average-height parents give birth to a child exhibiting achondroplastic dwarfism, it is most likely due to a new mutation. This is because _____.
the frequency of achondroplasia is unknown achondroplasia is a relatively rare disorder achondroplasia is caused by an allele that is always expressed, so the parents couldn't have the allele such mutations are statistically predictable none of the above |
achondroplasia is caused by an allele that is always expressed, so the parents couldn't have the allele
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Cystic fibrosis, which is usually lethal before the age of reproduction, is a homozygous recessive trait. Why do cases continue to arise, even though people with the disease rarely reproduce?
because new mutations continually introduce this harmful condition into the population because the harmful allele "hides" inside heterozygous individuals and 1/4 of the offspring of two heterozygotes should be afflicted because mosquitoes can transfer the disease from person to person because people continue to make inappropriate lifestyle choices none of the above |
because the harmful allele "hides" inside heterozygous individuals and 1/4 of the offspring of two heterozygotes should be afflicted
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It is far more common to find human genetic disease caused by __________ alleles than by __________ alleles because __________.
dominant ... recessive ... individuals with dominant alleles have an advantage over individuals with recessive alleles dominant ... recessive ... dominant alleles became dominant because they aid the survival of the organism carrying them recessive ... dominant ... harmful recessive alleles can survive in the heterozygote without causing any adverse effects on the phenotype recessive ... dominant ... even when homozygous, recessive alleles usually do not cause as much damage as dominant alleles none of the above |
recessive ... dominant ... harmful recessive alleles can survive in the heterozygote without causing any adverse effects on the phenotype
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Michelle and Keith are apparently normal, but their daughter was born with alkaptonuria, an inherited metabolic disorder. If alkaptonuria is like most other human hereditary disorders, the probability of their next child being born with alkaptonuria is _____.
0 0.25 0.50 0.75 1.0 |
0.25
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Huntington's disease is an example of a genetic disorder caused by _____.
a late-acting lethal dominant allele a nonlethal dominant allele a late-acting recessive allele homozygous recessive alleles multiple alleles |
a late-acting lethal dominant allele
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Several inherited disorders are much more common in close-knit religious communities, such as the Amish, than in the general population. This is at least partly due to the fact that _____.
people in such communities are more likely to marry relatives shared environmental conditions such as diet can increase mutation rate modern medical care is not widely available in such communities community members care for each other, and such disorders are contagious individuals in such communities are more likely to have large families |
people in such communities are more likely to marry relatives
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Fetal cells may be removed along with fluid from the womb by a process known as _____.
karyotyping uterine tapping amniocentesis ultrasound imaging chorionic villus sampling |
amniocentesis
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A red bull is crossed with a white cow and all of the offspring are roan, a shade between red and white. This is an example of genes that are _____.
nonhomologous epistatic codominant incompletely dominant completely dominant |
incompletely dominant
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Flower color in snapdragons is an example of incomplete dominance. If a red-flowered plant is crossed with a white-flowered plant, the F1 generation has pink flowers. If a pink-flowered plant is crossed with a pink-flowered plant, the progeny plants will be __________.
100% pink 100% red 25% red, 50% pink, and 25% white 50% pink and 50% red 25% white and 75% red |
25% red, 50% pink, and 25% white
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A man who has type B blood and a woman who has type A blood could have children of which of the following phenotypes?
A or B only AB only AB or O A, B, or O A, B, AB, or O |
A, B, AB, or O
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Which of the following matings can NOT produce a child with blood type O? The letters refer to blood types (phenotypes).
A x A A x B O x AB O x O all of the above |
O x AB
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If one parent is blood type AB and the other is type O, what fraction of their offspring will be blood type A?
0.25 0.5 0.75 all of the above none of the above |
0.5
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A woman with type O blood is expecting a child. Her husband is type A. Both the woman's father and her husband's father had type B blood. What is the probability that the child will have type O blood?
100% 75% 50% 25% 0% |
50%
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A single allele that controls more than one character is said to be _____.
polygenic photogenic pleiotropic autotrophic linked |
polygenic
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In people with sickle-cell disease the red blood cells break down, clump, and clog the blood vessels. The blood vessels and the broken cells accumulate in the spleen. Among other things this leads to physical weakness, heart failure, pain, and brain damage. Such a suite of symptoms can be explained by _____.
the polygenic nature of sickle-cell disease the pleiotropic effects of the sickle-cell allele the disease being the result of the inheritance of two linked genes a bacterial infection interacting with the sickle-cell allele side effects of the drugs used to cure sickle-cell disease |
the pleiotropic effects of the sickle-cell allele
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The inheritance of height and weight can best be described as _____.
simple dominant-recessive inheritance being caused by microorganisms polygenic all symptoms of Huntington's disease the results of a bad lifestyle |
polygenic
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Seeds from a single sexually reproducing plant are harvested and later planted under identical conditions. What results should be expected?
The seedlings should be identical to each other but not to the parental plant. The seedlings should be identical to each other and to the parental plant. The seedlings should differ from each other, depending on the environmental conditions under which each is planted. The seedlings should differ from each other, depending on their genetic constitution. The seedlings should differ from each other and be identical to the parental plant. |
The seedlings should differ from each other, depending on their genetic constitution.
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The genetic test that is used to determine whether someone possesses a potentially harmful recessive allele is referred to as _____ testing.
prenatal testing carrier testing predictive testing diagnostic testing newborn screening |
carrier testing
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If two genes are linked _____.
they are on different chromosomes they assort independently they code for the same protein they are on the same chromosome they are on sex chromosomes |
they are on the same chromosome
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If hair color, eye color, and the presence or absence of freckles were consistently inherited together, the best explanation would be that _____.
these traits are recessive characteristics both parents have the same hair color, eye color, and freckles the genes for these traits are linked on the same chromosome gene duplications have occurred these traits are dominant to others |
the genes for these traits are linked on the same chromosome
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If the two traits that Mendel looked at in his dihybrid cross of smooth yellow peas with wrinkled green peas had been controlled by genes that were located close together on the same chromosome, then the F2 generation _____.
would have contained four phenotypes in a 9:3:3:1 ratio would have contained only individuals that were heterozygous for both genes would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment would have contained no individuals that were heterozygous for both genes none of the above |
would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment
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In a particular species of mammal, black hair (B) is dominant to green hair (b), and red eyes (R) are dominant to white eyes (r). When a BbRr individual is mated with a bbrr individual, offspring are produced in a ratio of 5 black hair and red eyes : 5 green hair and white eyes : 1 black hair and white eyes : I green hair and red eyes. Which of these explanations accounts for this ratio?
Green-haired individuals have a higher prenatal mortality than black-haired individuals. The genes for hair color and the genes for eye color are carried on different chromosomes. The expected results did not take genetic recombination into account. The genes for both of these traits are carried on the autosomes. The genes for hair color and eye color are linked. |
The genes for hair color and eye color are linked.
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In question 46, the observed distribution of offspring was: black-red 1,070; black-white 177; green-red 180; green-white 1,072. Based on these data, what is the recombination frequency?
86% 7 17% 14% 30% |
14%
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Sturtevant's genetic mapping _____.
orders genes on a chromosome based on recombination frequencies can be constructed only for sex chromosomes orders genes on a chromosome based on their location with respect to a stained band shows the ordering and exact spacing of genes on a chromosome predicts the probability that you will have a male or female child |
orders genes on a chromosome based on recombination frequencies
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The crossover percentage between two different genes is _____.
dependent on the sex of the parent greater as the distance between the two genes increases greater as the distance between the two genes decreases dependent on whether dominant or recessive alleles are carried by the two genes equal to the size of the chromosome |
greater as the distance between the two genes decreases
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The Y chromosomes of mammals contain genes that code for ____________.
eye pigment, among many other traits blood-clotting factor, among many other traits "maleness" and few other traits both eye pigment and blood-clotting factor, among many other traits criminal tendencies |
"maleness" and few other traits
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In an important experiment, radioactively labeled bacteriophages were allowed to infect bacteria. In the first trial, the phages contained radioactive DNA, and radioactivity was detected in the bacteria. Next, other phages containing radioactive protein were allowed to infect bacteria, and radioactivity was not detected in the bacteria. These experiments led to the conclusion that _____.
the genes of this phage were made of DNA bacteriophages can infect bacteria DNA is made of nucleotides genes carry information for making proteins genes are on chromosomes |
the genes of this phage were made of DNA
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Scientists have discovered how to put together a bacteriophage with the protein coat of phage T2 and the DNA of phage T4. If this composite phage were allowed to infect a bacterium, the phages produced in the host cell would have _____.
the protein of T2 and the DNA of T4 the protein of T4 and the DNA of T2 a mixture of the DNA and proteins of both phages the protein and DNA of T2 the protein and DNA of T4 |
the protein and DNA of T4
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Which one of the following lists the four bases contained in DNA?
cytosine, guanine, thymine, uracil adenine, guanine, uracil, thymine guanine, pyroline, thymine, uracil adenine, guanine, purine, thymine adenine, guanine, cytosine, thymine |
adenine, guanine, cytosine, thymine
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Which one of the following describes a nucleotide most completely?
a sugar and a phosphate group only nitrogen base and a sugar only nitrogen base, a sugar, and a phosphate group a sugar and a pyrimidine a sugar and a purine |
nitrogen base, a sugar, and a phosphate group
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What technique was most helpful to Watson and Crick?
radioactive labeling X-ray crystallography electrophoresis cloned DNA transgenic animals |
X-ray crystallography
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Chargaff found that for DNA _____.
the ratio of A to C is close to 1:1 and the ratio of G to T is close to 1:1 the ratio of A to T is close to 1:1 and the ratio of G to C is close to 1:1 the ratio of A to G is close to 1:1 and the ratio of T to C is close to 1:1 A + T = G + C A + G > T + C |
the ratio of A to T is close to 1:1 and the ratio of G to C is close to 1:1
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One strand of a DNA molecule has the base sequence ATAGGT. The complementary base sequence on the other strand of DNA will be _____.
TATCCA TGGATA TGGAUA UAUCCA ATAGGT |
TATCCA
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The two sugar-phosphate strands of a DNA molecule are joined to each other through _____.
5' —> 3' deoxyribose and phosphate bonds hydrogen bonds between nucleotide bases covalent bonds between nitrogen atoms in adenine and in thymine covalent bonds between carbon atoms in deoxyribose molecules ionic bonds between guanine and cytosine |
hydrogen bonds between nucleotide bases
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Who is generally credited with discovering that the DNA molecule is constructed as a double helix?
Jacob and Monod Watson and Crick Pauling Davson and Danieli Hershey and Chase |
Watson and Crick
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Which one of the following accurately reflects complementary base pairing in the DNA molecule?
guanine–cytosine guanine–adenine cytosine–thymine uracil–thymine adenine–cytosine |
guanine–cytosine
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Which one of the following is NOT true about double-stranded DNA?
It is helical. It contains hydrogen bonds. The two strands are said to be complementary. Adenine and uracil are present in equal amounts. The strands run in opposite directions. |
Adenine and uracil are present in equal amounts.
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The information in DNA is contained in _____.
the variation in the structure of nucleotides that make up the DNA molecule the type of sugars used in making the DNA molecule the sequence of amino acids that make up the DNA molecule the sequence of nucleotides along the length of one strand of the DNA molecule all of these |
the sequence of nucleotides along the length of one strand of the DNA molecule
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Which one of the following statements does NOT apply to the Watson-Crick model for DNA?
The two strands of the DNA helix run in opposite directions. The purines (double rings) base pair with the pyrimidines (single rings). The two strands of the helix are held together by covalent bonds. The framework of the helix consists of sugar-phosphate units of the nucleotides. The nitrogenous bases are attached to the deoxyribose molecules. |
The two strands of the helix are held together by covalent bonds.
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The statement that each new molecule of DNA contains one parental and one newly synthesized strand of DNA refers to _____.
the one gene–one enzyme hypothesis the de novo synthesis of DNA Chargaff's rule about DNA a model of DNA replication the formation of replication bubbles |
a model of DNA replication
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During the replication of DNA molecules _____.
both strands of a molecule act as templates the reaction is catalyzed by RNA polymerase errors never occur only one strand of the molecule acts as a template the cell undergoes mitosis |
both strands of a molecule act as templates
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Two new strands of DNA molecules grow as bases are added by the enzyme _____.
bacterial duplicating complex DNA polymerase DNA replicase RNA polymerase polynucleotidase |
DNA polymerase
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The role of DNA polymerases in DNA replication is to _____.
attach free nucleotides to the new strand disassemble nucleotides from the original strand to make a new strand bind together short strands break the hydrogen bonds that hold the nucleotides together "unzip" the DNA molecule |
attach free nucleotides to the new strand
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What enzyme joins DNA fragments?
DNA polymerase DNA ligase topoisomerase RNA polymerase primase |
DNA ligase
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Monomers for the synthesis of DNA are called _____.
amino acids fatty acids nucleotides monosaccharides disaccharides |
nucleotides
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One strand of DNA has the following sequence of nucleotides: 3'-ATTCGCTAT-5' The base sequence on the other strand of DNA would be _____.
5'-ATTCGCTAT-3' 3'-ATTCGCTAT-5' 5'-TAAGCGATA-3' 3'-TAAGCGATA-5' 5'-GCCTATCGG-3' |
5'-TAAGCGATA-3'
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Which description of DNA replication is correct?
A polymerase constructs a new strand alongside each old one by pairing complementary nucleotides. Ligase assembles single-stranded codons; then polymerase knits these codons together into a DNA strand. The two strands of DNA separate, and restriction enzymes cut up one strand. Then polymerase synthesizes two new strands out of the old ones. The two strands separate and each one gets a complementary strand of RNA. Then this RNA serves as a template for the assembly of many new strands of DNA. None of these is correct. |
A polymerase constructs a new strand alongside each old one by pairing complementary nucleotides.
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A gene is usually _____.
the same thing as a chromosome the information for making a polypeptide made of RNA made by a ribosome made of protein |
the information for making a polypeptide
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Who of the following formulated the one gene–one enzyme hypothesis?
Watson and Crick Beadle and Tatum Hershey and Chase Franklin none of the above |
Beadle and Tatum
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Which one of the following is NOT associated with RNA?
a sugar thymine uracil phosphates single-strandedness |
thymine
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When messenger RNA (mRNA) is being made, the RNA base ____ always pairs with the base _____ in DNA.
U ... T T ... G U ... A A ... U T ... A |
U ... A
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The DNA code is CGT. What messenger RNA is made from this?
ATU GCA TCU CTA UCG |
GCA
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Information is transferred from the nucleus to the cytoplasm of eukaryotic cells in the form of _____.
proteins lipids nucleic acids carbohydrates sterols |
nucleic acids
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A particular ____ carry the information for making a specific polypeptide, but ____ can be used to make any polypeptide.
gene and ribosome ... tRNA and mRNA gene and mRNA ... a ribosome and tRNA ribosome and mRNA ... a gene and tRNA gene and tRNA ... a ribosome and mRNA tRNA and ribosome ... a gene and mRNA |
gene and mRNA ... a ribosome and tRNA
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The number of nucleotide bases "read" together on the mRNA to designate each amino acid is __________; this unit is called a __________.
2 ... dipeptide 3 ... triose 2 ... anticodon 3... codon 1 ... amino acid |
3... codon
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Which one of the following statements is true?
Each DNA base codes for three amino acids. Each gene codes for three proteins. It takes three genes to code for one protein. Each triplet has many different meanings. Each amino acid in a protein is coded for by three bases in the DNA. |
Each amino acid in a protein is coded for by three bases in the DNA.
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There are six different codons signaling for the placement of the amino acid leucine in a protein. Because of this, we say that the code is _____.
inaccurate incomplete specific redundant tricky |
redundant
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During the transcription of a given portion of a DNA molecule _____.
mRNA is synthesized on both chains of the DNA molecule at once mRNA is synthesized on both chains of the DNA molecule, but first on one side and then the other mRNA is synthesized on only one of the chains half of the mRNA is synthesized on half of one chain; then the other half of the mRNA is made on the other half of the DNA any of the above patterns may be found |
mRNA is synthesized on only one of the chains
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One strand of a DNA molecule has the following sequence: 3'-AGTACAAACTATCCACCGTC-5'. In order for transcription to occur in that strand, there would have to be a specific recognition sequence, called a(n) __________, to the left of the DNA sequence indicated.
centromere intron exon AUG codon promoter |
promoter
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At one point as a cell carried out its day-to-day activities, the nucleotides GAT were paired with the nucleotides CUA. This pairing occurred _____.
in a double-stranded DNA molecule during translation during transcription when an mRNA codon paired with a tRNA anticodon it is impossible to say, given this information |
during transcription
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A terminator in mRNA synthesis is _____.
an enzyme whose specific function is to stop synthesis a molecule of tRNA that recognizes a stop codon a specific nucleotide sequence in DNA that signals a stop A character played by Arnold Schwarzenegger none of the above |
a specific nucleotide sequence in DNA that signals a stop
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Which one of the following catalyzes the linkage between nucleotides to form RNA?
RNA polymerase RNA ligase RNA reverse transcriptase tRNA |
RNA polymerase
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In transcription, _____.
the DNA promoter region acts as an initial binding site for RNA polymerase only one DNA strand is used as a template for the synthesis of RNA RNA nucleotides are used all of the above none of the above |
all of the above
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What is the proper order of the following events in the expression of a eukaryotic gene?
translation RNA processing transcription 1, 2, 3 3, 2, 1 2, 3, 1 2, 3, 1 1, 2, 3 |
3, 2, 1
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A cell biologist found that two different proteins with largely different structures were translated from two different mRNAs. These mRNAs, however, were transcribed from the same gene in the cell nucleus. Which mechanism below could best account for this?
Different systems of DNA unpacking could result in two different mRNAs. A mutation might have altered the gene. Exons from the same gene could be spliced in different ways to make different mRNAs. The gene could be transcribed in different directions. The two proteins have different functions in the cell. |
Exons from the same gene could be spliced in different ways to make different mRNAs
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Usually, in eukaryotic genes _____.
exons are not transcribed introns are not transcribed exons are transcribed, but the RNA transcribed from introns does not leave the nucleus both introns and exons are transcribed, but the RNA transcribed from introns does not leave the nucleus exons and introns are transcribed, and the RNA transcribed from them leaves the nucleus |
both introns and exons are transcribed, but the RNA transcribed from introns does
not leave the nucleus |
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Which one of the following statements correctly describes mRNA processing in eukaryotes?
Introns are cut out and the resulting exons are spliced together. Exons are cut out and the introns are spliced together. Introns are cut out and spliced together at the end of the mRNA. Exons are cut out and transported to smooth endoplasmic reticulum. Introns are cut out and transported to the ribosomes. |
Introns are cut out and the resulting exons are spliced together.
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A base-substitution mutation in a germ cell line is likely to have NO effect on phenotype if the substitution _____.
forms a new stop codon occurs in an intron changes a stop codon to a codon specifying an amino acid substantially changes the structure of an enzyme prevents the initiation of transcription of the DNA sequence that codes for ATP synthase |
occurs in an intron
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In a eukaryotic cell, transcription takes place _____.
on the cell membrane in the rough endoplasmic reticulum in the cytoplasm on free ribosomes in the nucleus |
in the nucleus
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The function of tRNA during protein synthesis is to _____.
deliver amino acids to their proper site during protein synthesis guide ribosome subunits out of the nucleus through nuclear pores attach mRNA to the small subunit of the ribosome process mRNA transcribe mRNA |
deliver amino acids to their proper site during protein synthesis
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The nucleotide sequence of a DNA codon is GTA. A messenger RNA molecule with a complementary codon is transcribed from the DNA. In the process of protein synthesis, a transfer RNA pairs with the mRNA codon. What is the nucleotide sequence of the tRNA anticodon?
CAT CUT GUA CAU GTA |
GUA
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The bonds that hold tRNA molecules in the correct three-dimensional shape are _____.
peptide linkages hydrophobic interactions covalent bonds ionic bonds hydrogen bonds |
hydrogen bonds
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During translation in a eukaryotic cell _____.
ribosomes move into the nucleus tRNA carries amino acid molecules to the nucleus, where they are added to a growing polypeptide chain polypeptides are synthesized at ribosomes, according to instructions carried by mRNA mRNA is synthesized by the bonding of free nucleotides to the bases on the template strand of DNA French cells are able to speak to German cells |
polypeptides are synthesized at ribosomes, according to instructions carried by mRNA
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The P site of a ribosome does which one of the following?
It holds the tRNA that is carrying the next amino acid to be added to the growing polypeptide chain. It holds the growing polypeptide chain. It helps "unzip" DNA during transcription. It catalyzes the addition of amino acids to the polypeptide chain of adjacent amino acids. It recognizes the promoter during transcription initiation. |
It holds the growing polypeptide chain.
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Which one of the following processes does NOT take place in the nucleus?
replication of DNA translation assembly of ribosomal subunits removal of introns from RNA transcription |
translation
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The first amino acid inserted into a new polypeptide chain in eukaryotic cells is always _____.
glycine serine methionine tryptophan alanine |
methionine
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During translation, amino acid chain elongation occurs until _____.
no further amino acids are needed by the cell all tRNAs are empty the polypeptide is long enough the ribosome encounters "stop" codons the ribosome runs off the end of the mRNA strand |
the ribosome encounters "stop" codons
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A virus infects a cell and randomly inserts many short segments of DNA containing a stop codon throughout the organism's chromosomes. This will probably cause _____.
manufactured proteins to be short and defective the DNA to break up into thousands of short segments incorrect pairing between mRNA codons and amino acids no bad effects, as long as the stop codons are not also inserted into tRNA all of the above |
manufactured proteins to be short and defective
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During the process of translation, ____ matches an mRNA codon with the proper amino acid.
a ribosome DNA polymerase GTP transfer RNA messenger RNA |
transfer RNA
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A sequence of pictures of polypeptide synthesis shows a ribosome holding two transfer RNAs. One tRNA has a polypeptide chain attached to it; the other tRNA has a single amino acid attached to it. What does the next picture show?
The polypeptide chain moves over and bonds to the single amino acid. The tRNA with the single amino acid leaves the ribosome. The amino acid moves over and bonds to the polypeptide chain. The tRNA with the polypeptide chain leaves the ribosome. A third tRNA with an amino acid joins the pair on the ribosome. |
The polypeptide chain moves over and bonds to the single amino acid.
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Which brief outline of protein synthesis is correct?
DNA leaves the nucleus, goes to a ribosome, and catalyzes the polymerization of amino acids in a protein. DNA exchanges its thymine units with uracil in polymerase. This activates polymerase, and it starts joining amino acids together. Transfer RNAs line up on a ribosome, and amino acids bind to them with hydrogen bonds. Messenger RNA is made on a DNA template, and then amino-acid-bearing transfer RNAs line up on it in through codon-anticodon pairing. None of the above. |
Messenger RNA is made on a DNA template, and then amino-acid-bearing transfer RNAs line up on it in through codon-anticodon pairing
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Mutations are _________.
changes in the composition of a DNA molecule changes in genes that ultimately cause genetic diversity the source of new alleles chemical changes in the genetic material all of the above |
all of the above
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A geneticist found that a particular mutation had no effect on the polypeptide encoded by a gene. This mutation probably involved _____.
deletion of one nucleotide alteration of the start codon insertion of one nucleotide deletion of the entire gene substitution of one nucleotide |
substitution of one nucleotide
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Imagine an error occurring during DNA replication in a cell, so that where there is supposed to be a T in one of the genes, there is instead a G. What effect will this probably have on the cell?
Each of its kinds of proteins will contain an incorrect amino acid. An amino acid will be missing from each of its kinds of proteins. One of its kinds of proteins might contain an incorrect amino acid. An amino acid will be missing from one of its kinds of proteins. The amino acid sequence of one of its kinds of proteins will be completely changed. |
One of its kinds of proteins might contain an incorrect amino acid.
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Ultraviolet (UV) radiation is damaging because it ____________.
prevents DNA transcription prevents DNA translation causes mutations in the DNA deactivates the enzymes needed for DNA replication inhibits protein synthesis |
causes mutations in the DNA
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Genetic mutations _____.
can occur naturally are most common in body parts that are not used very often are most common in body parts that are used frequently are mainly caused by diseases associated with fetal development are always passed on to the next generation |
can occur naturally
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When a bacteriophage infects an E. coli cell, what part of the phage enters the bacterial cytoplasm?
the whole phage only nucleic acid the coat and its enclosed nucleic acid the cell wall the membranous envelope |
only nucleic acid
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The phage reproductive cycle that kills the bacterial host cell is a _____ cycle.
lytic replicative lysogenic transcriptional translational |
lytic
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A prophage is a(n) _____.
emerging virus virus that infects bacteria type of retrovirus prion that has been integrated into a bacterial cell's chromosome viral genetic material that has been incorporated into a bacterial cell's chromosome |
viral genetic material that has been incorporated into a bacterial cell's chromosome
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In the lytic life cycle of phages _____.
the nucleic acid of the phage is all that enters the host cell the viral coat is assembled according to the genetic information of the bacterium the entire phage is taken into the bacterium DNA replication is not part of the life cycle phage DNA is incorporated into the host cell's chromosome |
the nucleic acid of the phage is all that enters the host cell
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In the lysogenic cycle of phages _____.
the nucleic acid of the phage is all that enters the host cell the viral coat is assembled according to the genetic information of the viral nucleic acid the viral nucleic acid can insert itself into the host chromosome the viral nucleic acid is replicated with the host DNA all of the above |
all of the above
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A microbiologist analyzed chemicals obtained from an enveloped RNA virus—similar to a mumps virus—that infects monkeys. He found that the viral envelope contained a protein characteristic of monkey cells. Which of the following is the most likely explanation?
The virus gets an envelope when it leaves the host cell. The virus forced the monkey cell to make proteins for its envelope. The virus is a prophage. Its presence is a result of the monkey's immunological response. The virus fools its host by mimicking its proteins. |
The virus gets an envelope when it leaves the host cell.
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Which of these is classified as an emerging virus that can have a direct impact on human health?
lambda tobacco mosaic virus pneumonia Ebola T2 |
Ebola
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How do retroviruses such as HIV differ from other viruses?
They have much simpler reproductive cycles than other RNA viruses. They contain DNA that is used as a template to make RNA. They can reproduce only inside living cells. They contain nucleic acids that code for proteins. They contain the enzyme reverse transcriptase |
They contain the enzyme reverse transcriptase
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Reverse transcription, carried out by retroviruses, is the process by which _____.
DNA information is copied into RNA RNA information is copied into DNA RNA information is "read" to form a protein molecule DNA is duplicated information is copied from a protein molecule into RNA |
RNA information is copied into DNA
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In general, the lactose operon __________.
continuously produces the enzymes for lactose utilization until all of the lactose is used up is transcribed only in the presence of lactose is transcribed when lactose binds to the lactose repressor protein is unable to be transcribed if only the lactose repressor is present all of the above |
all of the above
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In prokaryotes, a group of genes with related functions is called __________.
an operon constitutive a repressor an activator RNA polymerase |
an operon
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The promoter of an operon _____.
is where an RNA polymerase first binds is where a DNA polymerase first binds is a site of termination of RNA synthesis is a site of termination of protein synthesis codes for enzymes |
is where an RNA polymerase first binds
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Operons function in prokaryotes to _____.
regulate the catalytic activities of specific proteins regulate the rate of transcription phosphorylate specific polypeptide chains degrade proteins none of the above |
regulate the rate of transcription
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You have inserted the gene for human growth factor into the E. coli lactose operon, replacing the structural genes with the gene for human growth factor. What substance must you add to your culture of bacteria to cause them to produce human growth factor for you?
repressor protein operator protein human growth factor lactose any of the above substances will work |
lactose
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The lactose operon (lac operon) in the bacterium E. coli is turned on in the presence of _____.
glucose lactose sucrose fructose galactose |
lactose
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When a certain bacterium encounters the antibiotic tetracycline, the antibiotic molecule enters the cell and attaches to a repressor protein. This keeps the repressor from binding to the bacterial chromosome, allowing a set of genes to be transcribed. The transcription of the genes is under the control of a(n) _____.
exon promoter operon homeobox nucleosome |
operon
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A bacterium can make the amino acid glycine or absorb it from its surroundings. A biochemist found that glycine binds to a repressor protein and causes the repressor to bind to the bacterial chromosome, turning off an operon. If it is like other operons, the presence of glycine will result in the _____.
inhibition of bacterial cell division breakdown of glycine cessation of the synthesis of glycine formation of sex pili manufacture of the repressor protein |
cessation of the synthesis of glycine
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Operons _____.
function in frequently changing environments function at the translation level of regulation correct mutations that might interfere with their genetic instructions degrade and recycle protein mutate and evolve more rapidly than other DNA sequences |
function in frequently changing environments
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The control of gene expression is more complex in multicellular eukaryotes than in prokaryotes because _____.
eukaryotic cells are much smaller in a multicellular eukaryote, different cells are specialized for different functions prokaryotes are restricted to stable environments eukaryotic chromosomes have fewer nucleotides, so each nucleotide sequence must do several jobs the genes of eukaryotes provide information for making proteins |
in a multicellular eukaryote, different cells are specialized for different functions
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The process by which cells become specialized is called __________.
apoptosis signal transduction divergence differentiation alternate RNA splicing |
differentiation
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Your muscle and bone cells are different because _____.
they contain different sets of genes they are differentiated they contain different operons different genes are switched on and off in each type of cell they contain different histones |
different genes are switched on and off in each type of cell
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Experiments involving _____ have demonstrated that differentiated cells contain all of the genetic information found in undifferentiated cells.
alternative RNA splicing operons RNA polymerase signal-transduction pathways nuclear transplantation |
nuclear transplantation
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In frogs, when the nucleus of an intestinal cell of a tadpole is transferred to an egg whose nucleus has been removed (nuclear transplantation), some of the eggs will develop into normal tadpoles. This demonstrates _____.
that frogs have meristematic cells that intestinal cells are not differentiated that these cells have retained all of their genetic potential that frogs have large eggs that these cells could not dedifferentiate |
that these cells have retained all of their genetic potential
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In eukaryotes, DNA packing seems to affect gene expression primarily by _____.
controlling access to DNA positioning related genes near each other protecting DNA from mutations enhancing the recombination of genes allowing unpacked genes to be eliminated from the genome |
controlling access to DNA
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In eukaryotes, the structures consisting of associations of histones and DNA are called _____.
histosomes nucleosomes ribosomes genetosomes dinasomes |
nucleosomes
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One of the functions of nucleosomes, structures in the nucleus, is to _____.
bind to and help process mRNA after it has been synthesized plug the nuclear pores except when specifically recognized molecules pass through wrap the DNA to organize it and make it more compact so that a large amount of DNA can fit into a cell nucleus synthesize ribosomes do all of these |
wrap the DNA to organize it and make it more compact so that a large amount of DNA can fit into a cell nucleus
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A genetic defect in humans results in the absence of sweat glands in the skin. Some men have this defect all over their bodies, but in women it is usually expressed in a peculiar way: A woman with this defect typically has small patches of skin with sweat glands and other patches without sweat glands. In women, the pattern of sweat-gland distribution can best be explained by _____.
a mutation X-chromosome inactivation alternate RNA splicing an operon a homeotic gene |
X-chromosome inactivation
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Dioxin, produced as a by-product of various industrial chemical processes, is suspected of causing cancer and birth defects in animals and humans. It apparently acts by entering cells and binding to proteins, altering the pattern of gene expression. Therefore, dioxin acts by mimicking the action of _____.
proteins of the mitochondria DNA polymerase transcription factors enhancers histones |
transcription factors
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In a eukaryote, a repressor protein may block gene expression by binding to a DNA site called a(n) _____.
operon histone enhancer promoter silencer |
silencer
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Gene expression in eukaryotes seems to be regulated largely by _____.
controlling gene packing and unpacking controlling the transcription of genes controlling the translation of mRNA into protein transcription factors encoded for by mitochondrial DNA selectively breaking down certain proteins so they cannot function |
controlling the transcription of genes
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Which of the following is true of gene regulation in both eukaryotes and prokaryotes?
elaborate packing of DNA in chromosomes transcription is the usual point at which gene expression is regulated the addition of a cap and a tail to mRNA lac and trp operons the removal of noncoding portions of RNA in the making of mRNA |
transcription is the usual point at which gene expression is regulated
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Enhancers __________.
increase the rate of transcription are found in eukaryotic DNA sequences may be located on either side of the gene they help regulate may be located at a considerable distance from the promoter all of the above |
all of the above
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Regions of noncoding DNA within a gene are called _____.
introns exons redundant coding sections oncogenes transcription factors |
introns
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Following transcription, mechanisms that regulate gene expression may include the __________.
initiation of translation breakdown of RNA activation of a protein initiation of translation and activation of a protein initiation of translation, breakdown of RNA, and activation of a protein |
initiation of translation, breakdown of RNA, and activation of a protein
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It is possible for a cell to make proteins that last for months; hemoglobin in red blood cells is a good example. However, many proteins are not this long-lasting. They may be degraded in days or even hours. Why do cells make proteins with such a short life?
Most proteins are used only once. Most cells in the body live only a few days. Cells lack the raw materials to make most of the proteins they need. Only cancer cells, which can keep dividing, contain long-lasting proteins. This enables cells to control the amount of protein present. |
This enables cells to control the amount of protein present.
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Which one of the following is NOT a means (or level) of controlling eukaryotic gene expression?
DNA packing transcriptional regulation mRNA processing requiring many protein factors in transcription all of the above play a role in the regulation of gene expression |
all of the above play a role in the regulation of gene expression
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Why, of all cell types, do embryonic stem (ES) cells have greatest potential for use in the treatment of disease?
They are impervious to carcinogens. They are undifferentiated cells that have the potential to differentiate into all of the different specialized cells of the body. They are larger and thus easier to work with than other cells. They are the most highly differentiated of all cell types. It is adult stem cells, not embryonic stem cells, that have the greatest potential for the treatment of disease. |
They are undifferentiated cells that have the potential to differentiate into all of the different specialized cells of the body.
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A homeotic gene does which of the following?
It serves as the ultimate control for the establishment of a head-to-tail axis. It regulates the expression of groups of other genes during development. It represses the histone proteins that package eukaryotic DNA. It helps splice mRNA after transcription. It inactivates one of the X chromosomes in a female mammal. |
It regulates the expression of groups of other genes during development.
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An animal's head-to-tail axis is established by _____
sperm cell mRNA proto-oncogenes egg cell mRNA tumor-suppressor genes homeotic genes |
egg cell mRNA
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The cellular response of a signal-transduction pathway that activates a transcription factor would be _____.
the synthesis of mRNA the activation of an inactive enzyme alteration of the cytoskeleton a change in the chemical composition of the cytosolic environment the activation of a metabolic pathway |
the synthesis of mRNA
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The region of homeotic genes that is virtually identical in every eukaryotic organism is the _____.
homeobox operon enhancer polypeptide promoters |
homeobox
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The similarity of the homeobox in many different kinds of organisms is evidence _____.
of convergent evolution of analogy that it is not responsive to natural selection of its recent origin of the common ancestry of different life forms |
of the common ancestry of different life forms
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Which one of the following best describes cancer cells?
Proto-oncogenes control their cell division. They will divide 20 to 50 times and then stop. They are more highly differentiated than normal cells. Normal controls over cell division have been altered. None of the above. |
Normal controls over cell division have been altered.
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The effect of oncogenes in human cells is __________.
to stimulate cell division to slow cell division to suppress tumors fewer cancers the repair of mutations so that cancers do not occur |
to stimulate cell division
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Which of these genes inhibit cell division?
homeotic genes proto-oncogenes operon genes tumor-suppressor gene nucleosomes |
tumor-suppressor gene
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A cancer cell _____.
is typically more than 10 times as large as a normal cell usually does not contain a nucleus does not respond to the signals that control cell division uses fewer nutrients than a normal cell is correctly described by all of the above |
does not respond to the signals that control cell division
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Most human cancers are __________.
caused by the accumulation of mutations caused by viruses inherited from one parent, like an autosomal dominant inherited from both parents, like an autosomal recessive caused by radiation |
caused by the accumulation of mutations
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In humans, most cancers are caused by _____.
tobacco vitamin E X-rays dietary fat UV radiation |
tobacco
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_____ is the leading cause of death in the United States.
Cancer AIDS Heart disease Homicide Suicide |
Heart disease
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Bacterial cells may integrate pieces of DNA from another cell in all of the following ways EXCEPT _____________.
transformation transduction conjugation binary fission all of these integrate pieces of DNA into a prokaryotic cell |
binary fission
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Sometimes a bacteriophage transfers a gene from one bacterium to another. This process is called _____.
transduction conjugation cloning binary fission transformation |
transduction
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A microbiologist found that a clone of bacteria infected by a phage had developed the ability to make a particular amino acid that the bacteria could not make before the infection. This new ability was probably a result of _____.
transformation natural selection conjugation spontaneous mutation transduction |
transduction
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An enzyme that "cuts" DNA at a specific sequence of bases is called _____.
reverse transcriptase restriction enzyme cDNA palindrome ligase |
restriction enzyme
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Bacteria use restriction enzymes to _____.
synthesize DNA synthesize RNA synthesize protein destroy foreign protein destroy foreign DNA |
destroy foreign DNA
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Which one of the following enzymes could create a bond between the adjacent, unjoined nucleotides?
DNA ligase reverse transcriptase restriction enzyme terminator enzyme DNA polymerase |
DNA ligase
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What two enzymes are needed to produce recombinant DNA?
a restriction enzyme and a catalase a restriction enzyme and a ligase a restriction enzyme and a polymerase a polymerase and a ligase a polymerase and a catalase |
a restriction enzyme and a ligase
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Restriction enzymes leave "sticky ends" when they cut a piece of DNA. The most useful result of this is that the sticky ends allow ____________.
the cut to be easily repaired by ligases the easy insertion of a foreign piece of DNA that has had its ends cut by the same restriction enzyme the cutting of a piece of DNA without the separation of the two strands the creation of a hybrid molecule in which one strand is DNA and the other strand is RNA all of the above |
the easy insertion of a foreign piece of DNA that has had its ends cut by the same restriction enzyme
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In genetic engineering "sticky ends" refers to _________.
a technique for finding a gene of interest within a nucleus without destroying the cell the ability of plasmids to stick to a bacterial cell wall and thus be taken up into the bacterium short bits of single-stranded DNA left at the end of a DNA molecule cut by a restriction enzyme the site on mRNA that sticks to the DNA it is transcribing none of the above |
short bits of single-stranded DNA left at the end of a DNA molecule cut by a restriction enzyme
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When a typical restriction enzyme cuts a DNA molecule, the cuts are staggered so that the DNA fragments have single-stranded ends. This is important in recombinant DNA work because _____.
it allows a cell to recognize fragments produced by the enzyme the single-stranded ends serve as starting points for DNA replication the fragments will bond to other fragments with complementary single-stranded ends it enables researchers to use the fragments as introns only single-stranded DNA segments can code for proteins |
the fragments will bond to other fragments with
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The so-called sticky ends of a plasmid or bacterial chromosome are ____________.
produced by methylation the result of reverse transcription unpaired bases produced by a restriction enzyme unpaired bases produced by DNA polymerase paired bases produced by DNA polymerase |
unpaired bases produced by a restriction enzyme
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DNA used in recombinant DNA techniques is first cut into fragments by _____.
enzymes called ligases restriction enzymes treatment with DNA polymerase treatment with a strong acid or base X-rays |
restriction enzymes
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In recombinant methods, the term "vector" refers to _____.
the enzyme that cuts DNA into restriction fragments the "sticky" ends of a DNA fragment restriction fragment a plasmid or other agent used to transfer DNA into a living cell a DNA probe used to locate a particular gene |
a plasmid or other agent used to transfer DNA into a living cell
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Much of genetic engineering uses plasmids, which are _____.
repeating sequences that protect DNA from digestion when it is inserted into a foreign cell small circlets of DNA found in bacteria segments of RNA that must be attached to DNA before the DNA can replicate ends of cut DNA molecules that are "sticky" because they have unpaired base sequences infectious proteins |
small circlets of DNA found in bacteria
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"Sticky ends" are very useful in genetic engineering because _____.
they provide a site for complementary base pairing so that pieces of DNA can be linked together they prevent the enzymatic degradation of engineered DNA they allow scientists to label genes in a living cell they allow scientists to use the edited form of mRNA for genetic engineering they serve as the means for getting recombinant DNA into another cell, such as a bacterium |
they provide a site for complementary base pairing so that pieces of DNA can be linked together
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What is gene cloning?
Gene cloning occurs when a phage transfers bacterial DNA from one bacterium to another. Gene cloning occurs when a bacterium takes up DNA from the surrounding fluid. Gene cloning occurs when a bacterium carrying a recombinant plasmid reproduces, thus allowing for the production of multiple copies of the recombinant plasmid. Gene cloning occurs when cDNA is produced from an mRNA template. Gene cloning is the direct transfer of DNA from one bacterium to another. |
Gene cloning occurs when a bacterium carrying a recombinant plasmid reproduces, thus allowing for the production of multiple copies of the recombinant plasmid.
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Copies of cloned genes are stored in a(n) _____.
gene bank plasmid eukaryotic cell supermarket genomic library |
genomic library
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Because eukaryotic genes contain introns, they cannot be translated by bacteria, which lack RNA-splicing machinery. If you want to engineer a bacterium to produce a eukaryotic protein, you can synthesize a gene without introns. If you know the nucleotide sequence you can _____.
alter the bacteria used so that they can splice RNA use a nucleic acid probe to find a gene without introns work backward from mRNA to make a version of the gene without introns use a phage to insert the desired gene into a bacterium use a restriction enzyme to remove introns from the gene |
work backward from mRNA to make a version of the gene without introns
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DNA synthesized using an RNA template is called _____.
reverse transcriptase a restriction enzyme cDNA a recognition sequence a plasmid |
cDNA
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What is the source of the reverse transcriptase used in recombinant DNA technology?
retroviruses artificial synthesis cultured fungal cells cultured phage-infected mammalian cells either retroviruses or cultured phage-infected mammalian cells |
retroviruses
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An enzyme that makes DNA from an RNA template is called ____________.
reverse transcriptase a restriction enzyme cDNA a recognition sequence ligase |
reverse transcriptase
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Putting a human gene into the plasmids of bacteria has enabled scientists to _____.
insert the corrected gene into patients who have certain genetic disorders use these bacteria to mass-produce mRNA for certain genes match DNA found at a crime scene to a suspect's DNA identify carriers of genetic diseases use bacteria as "factories" for protein products such as insulin |
use bacteria as "factories" for protein products such as insulin
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A nucleic acid probe is used to _____.
clone genes produce a large amount of DNA from a tiny amount make exact copies of DNA sequences identify genes that have been inserted into bacterial plasmids or separated by electrophoresis make DNA from RNA |
identify genes that have been inserted into bacterial plasmids or separated by electrophoresis
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Human nerve cells differ from human muscle cells because different sets of genes are expressed; in each type of cell, different genes are transcribed into mRNA and translated into protein. Which of the following would be the most efficient way to identify the genes that these cells express?
gel electrophoresis of DNA fragments DNA microarrays isolating and analyzing all the proteins from each type of tissue PCR chromosome walking |
DNA microarrays
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Electrophoresis is used to _____.
separate fragments of DNA clone genes cut DNA into fragments match a gene with its function amplify small DNA samples to obtain enough for analysis |
separate fragments of DNA
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Genetic engineers often insert marker genes into plasmids containing genes of interest so that ____________.
they will know which bacteria have taken up the plasmid the chances that the bacteria will take up the plasmid are greatly increased the circular plasmids will be transformed into linear segments of DNA that can be expressed the gene of interest will be automatically turned on once the bacteria take it up all of these will occur |
they will know which bacteria have taken up the plasmid
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DNA fingerprinting, a forensic procedure now being utilized to identify individuals, ____________.
is as good as actual fingerprints in recognizing individuals compares the DNA banding patterns of small segments of chromosomes compares the DNA banding patterns of entire chromosomes compares the DNA banding patterns of chromosomes in residues left by fingerprints can identify single individuals out of groups as large as 1 million individuals |
compares the DNA banding patterns of small segments of chromosomes
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A genetic marker is _____.
a place where a restriction enzyme cuts DNA a chart that traces the family history of a genetic trait a radioactive probe used to find a gene an enzyme used to cut DNA |
a particular nucleotide sequence whose inheritance can be followed
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DNA fingerprints are used to determine whether Sam could be the father of Becky's baby. Sam is not the father if ____ genetic fingerprint shows some bands not present in ____ genetic fingerprint.
Sam's ... the baby's Becky's ... the baby's the baby's ... Sam's the baby's ... Becky's the baby's ... Sam's or Becky's |
the baby's ... Sam's or Becky's
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DNA fingerprints used as evidence in a murder trial look something like supermarket bar codes. The pattern of bars in a DNA fingerprint shows _____.
the order of bases in a particular gene the presence of various-size fragments of DNA the presence of dominant or recessive alleles for particular traits the order of genes along particular chromosomes the exact location of a specific gene in a genomic library |
the presence of various-size fragments of DNA
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Gene therapy involves _____.
adding a functioning version of the defective gene to the cells of an individual allowing individuals to follow the natural progression of a genetic disorder, accompanied by psychological counseling, then treating with drugs only when the condition becomes life-threatening no serious ethical questions replacing organs affected with genetic disorders by transplants all of these |
adding a functioning version of the defective gene to the cells of an individual
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The polymerase chain reaction (PCR) is a useful technique because it can _____.
identify genetic markers for diseases make a large amount of DNA from a tiny amount establish paternity isolate particular genes of interest manufacture large amounts of a protein |
make a large amount of DNA from a tiny amount
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Potential benefits of the Human Genome Project include learning about _____.
embryonic development the treatment of diseases the prevention of diseases evolution all of these |
all of these
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A geneticist found a particular nucleotide sequence on different chromosomes in different mouse skin cells. This suggested that _____.
transformation was occurring in some skin cells transposons were moving around the DNA the cells were engaging in conjugation the mouse had been exposed to a mutagen the mouse responded to a vaccine |
transposons were moving around the DNA
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Which of the following would be considered a transgenic organism?
a bacterium that has received genes via conjugation a human given a corrected human blood-clotting gene a fern grown in cell culture from a single fern root cell a rat with rabbit hemoglobin genes a human treated with insulin produced by E. coli bacteria |
a rat with rabbit hemoglobin genes
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One problem with using the Ti plasmid as a vector to genetically modify agricultural plants is that _____.
new plant diseases have evolved faster than expected genetically engineered plants are very expensive the Ti plasmid does not work as a vector for grain-producing plant species most crop plants already grow at the maximum theoretical rate agricultural scientists have not pursued it seriously |
the Ti plasmid does not work as a vector for grain-producing plant species
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Print from here
The epithelial cells lining the intestine have surface projections that increase the area for absorption. These projections are called ________________. Villi Cilia Rugae Flagella Microvilli |
Microvilli
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Epithelial tissues are characterized as such because they
transmit impulses. cause body movements. cover both external and internal body surfaces. sense stimuli. form a framework that supports the body. |
cover both external and internal body surfaces
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Which muscle tissue is responsible for voluntary movement?
cardiac muscle only skeletal muscle only smooth muscle only cardiac and smooth muscle skeletal and smooth muscle |
skeletal muscle only
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Which of these is an example of positive feedback?
sweating when hot labor pains increasing in frequency and intensity drinking when thirsty shivering when cold eating when hungry |
labor pains increasing in frequency and intensity
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What kind of connective tissue has a liquid matrix?
cartilage nervous tissue loose connective tissue adipose tissue blood |
Blood
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The basic unit of nervous tissue is the
dendrite axon cell body neuron nerve |
neuron
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Structure in the living world is organized at hierarchal levels. Which of the following choices lists several of these, from least inclusive to most inclusive?
cell → organ → organ system → tissue → organism cell → tissue → organ → organ system → organism cell → organism → organ → organ system → tissue cell → organ system → tissue → organ → organism tissue → cell → organ system → organ → organism |
cell → tissue → organ → organ system → organism
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The main function of muscle tissue is __________.
sensation support contraction covering surfaces absorption |
contraction
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Which of the following is most likely to be responsible if your blood sugar were to come back down following a rise?
diabetes insipidus the use of the sugar for energy by your cells a homeostatic mechanism based on negative feedback type 2 diabetes you stopped exercising and drank some orange juice. |
a homeostatic mechanism based on negative feedback
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When body temperature is too low, which of the following occurs?
The thermostatic control center of the brain is deactivated. Blood vessels in the skin contract. Evaporative cooling occurs. Heat radiates from the skin. Blood vessels at the body surface fill with warm blood. |
Blood vessels in the skin contract.
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The organ in the body most responsible for maintaining water and salt balance is the __________.
small intestine pancreas kidney heart pineal gland |
kidney
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Which of the following neurons is part of the peripheral nervous system?
Sensory neuron and motor neuron Interneuron neuron and motor neuron Interneuron neuron and sensory neuron Only interneurons Only sensory neurons |
Sensory neuron and motor neuron
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The minimum change in a membrane's voltage that must occur to trigger an action potential is the ____________.
threshold minimum voltage voltage potential triggering charge triggering voltage |
threshold
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The movement of an action potential along a neuron is most like
the ripples created by dropping a pebble into a pond, gradually decreasing in size as the waves spread apart. a crowd at a sporting event doing the wave around a stadium. a radio tower emitting a signal that reaches only a small region. the sound of your voice spreading out as you yell loudly to your friend while at a park. the siren of an ambulance spreading out as the vehicle travels quickly down a highway. |
a crowd at a sporting event doing the wave around a stadium.
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Which of the following neurotransmitters is associated with sleep, mood, attention, and learning?
acetylcholine GABA Epinephrine Serotonin Endorphins |
Serotonin
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Arthritis is a common result of aging, affecting a person's ability to
catch their breath after exercise. move their joints. think clearly. heal broken bones. produce red blood cells. |
move their joints.
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Muscles are connected to bones by _____________.
thick filaments ligaments tendons other muscles myofibrils |
tendons
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Functionally, what is the muscle fiber's fundamental unit of contraction?
thick filament thin filament myofibril sarcomere Z line |
sarcomere
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At a chemical synapse, what causes the ion channels on the receiving cell's membrane to close?
No additional neurotransmitters are produced. The channels get plugged up with excessive neurotransmitters. The synaptic cleft pinches together, squeezing the channels closed. The neurotransmitter is broken down by an enzyme. Sodium ions rush back out of the receiving cell, causing the channel to close. |
The neurotransmitter is broken down by an enzyme.
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Digestion is the
absorption of nutrients. conversion of glycogen to glucose. mechanical and chemical breakdown of food. churning of food in the stomach and intestine. conversion of amino acids to proteins. |
mechanical and chemical breakdown of food.
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Muscular action propels food through the alimentary canal by a process called __________.
circular contractions diffusion active transport peristalsis progurgitation |
peristalsis
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How does Helicobacter pylori cause gastric ulcers in humans?
It neutralizes the acids of the stomach. It causes the production of excess acid in the stomach. H. pylori does not cause gastric ulcers. It damages the stomach's mucous coat. It eats away the lining of the mouth and throat. |
It damages the stomach's mucous coat.
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Which of the following mechanisms helps prevent the gastric juice from digesting the stomach lining?
pepsin breaking down proteins mucus lining the inside surface of the stomach mitosis generating enough new cells to replace the stomach lining every few days the continuous secretion of gastric juice the inactivation of pepsin by hydrochloric acid |
mucus lining the inside surface of the stomach
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Someone with liver failure will, in particular, have problems with the digestion and absorption of ___________.
minerals fats vitamins carbohydrates proteins |
fats
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Absorption of water is one major function of which of the following structures?
cecum esophagus appendix rectum colon |
colon
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The tongue does all of the following except ___________.
Taste food Manipulate food Shape food into a ball Secrete saliva Push food into the pharynx |
Secrete saliva
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Movement of food from the stomach into the esophagus is usually prevented by __________.
peristalsis reverse peristalsis the epiglottis a sphincter the pharynx |
a sphincter
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Which of the following is the usual cause of heartburn?
secretion of acid by the lining of the lower esophagus backflow of acid chyme from the stomach into the lower esophagus retention of food at the bottom of the esophagus by a sphincter that is reluctant to open irritation of the lower esophagus by substances in spicy food compression of the lower esophagus by an overfilled stomach |
backflow of acid chyme from the stomach into the lower esophagus
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Bile from the liver is stored in the _____________ before entering the intestine.
pancreas blood gallbladder intestinal wall common bile duct |
gallbladder
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The two major divisions of the nervous system are the _____________.
ANS and SNS Sympathetic and parasympathetic CNS and PNS Sensory and motor Voluntary and involuntary |
CNS and PNS
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