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187 Cards in this Set

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(Thomas Engelmann experiment)
An outcome of this experience was to help determine...
the relationship between wavelengths of light and the oxygen released during photosynthesis
What did he (Thomas Engelmann) conclude about the congregation of bacteria in the red and blue areas?
Bacteria congregated in these areas because these areas had the most oxygen being released
Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin Cycle?
ATP and NADPH
A new flower species has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed by this pigment?
red and yellow
The color of light least effective in driving photosynthesis is..
green
The reaction-center chlorophyll of photosystem I is known as P700 because..
this pigment is best at absorbing light with a wavelength of 700nm
All of the events listed below occur in the energy-capturing light reactions of photosunthesis except
carbon dioxide is incorporated in phosphoglycerate
The following statements about the light reactions of photosynthesis are all true except..
RUBP carboxylase is activated by photons
What is the primary function of the light reactions of photosynthesis?
to produce ATP and NADPH
Because bundle-sheath cells are relatively protected from atmospheric oxygen, the level of _________ is held to a minimum in C4 plants.
photorespiration
Which of the following statements regarding events in the functioning of photosystem II is falso?
The P680 chlorophyll donates a pair of protons to NADPH, which is thus converted to NADP+
Some photosynthetic organisms contain chloroplasts that lack phtotsystem II, yet are able to survive. The best way to detect the lack of photosystem II in these organisms would be...
to test for liberation of )2 in the light
Cyclic electron flow in the cholorplast produces..
ATP
Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?
the sythesis of ATP
In plant cells, ATP is made in response to light. An electron transport chain is involved. This electron transport chain is found in the..
thylakoid membranes of chloroplsats
As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from?
cyclic electron flow
Which of the following statements best describes the relationship between photosynthesis and respiration?
Photosynthesis stores energy in complex organic molecules, while respiration releases it.
Noncyclic photophosphorylation uses light energy to synthesize
ATP and NADPH
Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?
The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions
In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from
the stroma into the thylakoid compartment
In green plants, the primary function of the Calvin cycle is to..
contruct simple sugars from carbon dioxide
All of the following statements are correct regarding the Calvin cycle of photosynthesis except...
these reactions being soon after sundown and end before sunrise
*Oxidation of water*
photosynthesis
*Reduction of NADP+*
photosynthesis
*CO2 fixation*
photosynthesis
*synthesis of ATP by the chemiosmotic mechanism*
both photosynthesis and respiration
*generation of proton gradients across membranes*
both photosynthesis and respiration
*produces molecular oxygen*
light reactions alone
*requires ATP*
the calvin cycle alone
*requires ADP*
light reactions alone
*produces NADH*
neither the light reactions nor the Calvin cycle
*produces NADPH*
light reactions alone
*produces triose sugars*
the calvin cycle alone
*requires CO2*
the calvin cycle alone
Photorespiration lowers the efficiency of photosynthesis by removing which of the following from the calvin cycle?
ribulose biphosphate molecules
Why are C4 plants able to photosynthesize with no apparent photorespiration?
they use PEP carboxylase to initially fix CO2
Plants that fix CO2 into organic acids at night when the stoma are open and carry out the Calvin cycle during the day when the stoma are closed are called
CAM plants
Where does the Calvin cycle of photosynthesis take place?
strom of the chloroplast
A redox reaction involves the transfer of an..
electron
Which of the following sequences correctly represents the flow of electrons during photosynthesis?
H2O -> NADPH -> Calvin Cycle
The centromere is a region in which..
chromatids are attached to one another
A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei containing how many chromosomes?
46
All of the following occur during prometaphase of mitosis in animal cells except..
chromosomes are duplicated
Of the following, the best conclusion concerning the different between the S phases for beta and gamma is that..
gamma contains more DNA than beta
The best conclusion concerning delta is that the cells..
are actually in the G0 phase
Where do the microtubules of the spindle originate during mitosis in both plant and animal cells?
centrosome
Cytokinesis usually, but not always, follows mitosis. If a cell complete mitosis but not cytokinese, what would be the result?
a cell with two nuclei
REgarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants..
a cell plate begins to form at telophase. whereas in animals a cleavage furrow is initiated at that stage
Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, taxol disrupts mircotubule formation by binding to mircrotubules and accelerating their assembly from the protein precursor, tublin. Surprisingly, this stops mitosis. Specifically, taxol must affect..
the fibers of the mitotic spindle
If mammalian cells receive a go-ahead signal at teh G1 checkpoint, they will..
complete the cycle and divide
Cells that are in a nondividing state are in which phase?
G0
*released by platelets in the vicinity of an injury*
PDGF
*enzymes that activate or inactivate other proteins by phosphorylating them*
protein kinase
*fibroblasts have receptors for this substance on their plasma membranes*
PDGF
*a protein synthesized through the cell cycle that associates with a kinase to form active enzymes*
cyclin
*triggers the cell's passage past the G2 checkpoint into mitosis*
MPF
What tiggers the separation of chromatids during mitosis?
activation of an anaphase-promoting complex
Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called..
cyclins
"Density-dependent inhibition" is explained by which of the following?
As cells become more numerous, amount of required growth factors and nutrients per cell becomes insufficient to allow for cell growth
Which of the following is true concerning cancer cells?
A,B, and C are true
If the liver cells of an animal have 24 chromosomes, its sperm cells would have how many chromosomes?
12
Which of the following is true of a species that has a chromosome number of 2n-16?
A gamete from this species has 8 chromosomes
Which of the following is the term for a human cell that contains 22 pairs of autosomes and two X chromosomes?
A female somatic cell
All of the following are functions of meiosis in plants except...
production of identical daughter cells
Which of the following is missing from the life cycle listed below?
fertilization
In animals, somatic cells result from mitosis and______result from meiosis.
gametes
Which of the following happens at the conclusion of meiosis I?
homologous chromosomes are separated
Which of the following is true of the process of meiosis?
four haploid cells result
Which diagram represents late prophase I of meiosis?
IV
Which drawing represents anaphase of mitosis?
II
Which drawing represents metaphase II of meiosis?
VI
Which drawing represents a stage of meiosis where independent assortment might occur if there were more than one pair of chromosomes represented?
I
This occurs when a cell divides to form two nuclei that are genetically identical..
mitosis only
Homologoud chromosomes synapse and crossing over occurs..
meiosis I only
Centromeres uncouple and chromatids are separated from each other..
mitosis and meiosis II
Independent assortment of chromosomes occurs..
meiosis I only
Sequence of meiosis..
5,2,4,3,1
the chromosome makeup of a daughter cell at the completion of meiosis I..
B
the chromosome makeip of a daughter cell at the completion of meiosis II
C
How does the sexual life cycle increase the genetic variation in a species?
A, B, and C are correct
A plant with purple flowers is allowed to self-pollinate. Generation after generation, it produces pruple flowers. This is an example of..
true breeding
A cross between homozygous purple-flowered and homozygous white-flowered pea plants results in offspring with purple flowers. This demonstrates..
dominance
What was the most significant result Gregor Mendel drew from his experiments with pea plants?
Traits are inherited in discrete units, and are n ot the reults of "blending"
Alleles..
are the alternative forms of a gene
Mendel's law of segregations was nearly impossible for most biologists to understand until there was a general understanding of..
meiosis
A couple who are both carriers of the gene for cystic fibrosis have two children who have cystic fibrosis. What is the probability that their next child will have cystic fibrosis?
25%
In cattle, roan coat color...Which of the follwoing crosses could produce the hightest percentage of roan cattle?
red x white
The couple decides to have a second child. What is the probability that this child will be albino?
1/4 (always!)
For this trait, what is the genotype of the albino child?
homozygous recessive
What is the genotype of individual B-5?
ww only
What is the genotype of individual D-3?
Ww only
What is the probability that individual C-1 is Ww?
1
A sexually reproducing animal has two unlinked genes, one for head shape, and one for tail length. Which of the following genotypes is possible in a gamete from this organism?
HT
Two plants are crossed, resulting in offspring with a 3:1 ratio for a particular trait. This indicates...
that the parents were both heterozygous
If their first two children have normal pigmentations, what is the probability that their third child will e an albino?
1/4
What is the probability that their fourth child will have a homozygous genotpe?
1/2
Black fur in mice is dominant to brown fur. What fraction of the progeny of the cross will have black fur and long tails?
1/2
Tallness is dominant to dwarfness, while red flower color is dominant to white. What are the genotype and phenotype of the F1 individuals?
TtRr_tall and pink
In a dihybrid cross, the expected proportion of offspring showing both recessice traits is...
1/16
A 9:3:3:1 phenotypic ratio is characteristic of a..
dihybrid cross
A woman has 6 sons. The next chance that her next child will be a daughter is..
1/2
A 1:2:1 phenotypic ratio in the F2 generation of a monohybrid cross is a sign of..
incomplete dominance
Three babies were recently mixed up in a hospital. Which of the following represent the correct baby/parent combinations?
I-2, II-3, III-1
Which of the following is a possible genotype for the mother?
IAiRr
Which of the following is a possible phenotype for the father?
B positive
The ability of a single gene to have multiple phenotype effects..
pleiotrophy
One example is the ABO blood group system..
multiple alleles
The phenotype of the heterozygote differs from the phenotypes of both homozygotes..
incomplete dominance
Which of the following is a possible genotype for the son?
IBirr
Which of the following is an example of polygenic inheritance?
skin pigmentation in humans
Hydrangea plants of the same genotype are planted in a large flower garden. This can be best explained by..
environmental factors such as soil pH
People with sickle-cell trait..
all of the above are true
Substitution of the "wrong" amino acid in the hemoglobin protein results in this disorder..
sickle-cell disease
Individuals with this disorder are unable to metabolize gangliosides, affected individuals die early infancy..
Tay-Sachs disease
This is caused by a dominant single gene defect and generally does not appear until the individual is 30-40 years of age..
Huntington's disease
Effects of this recessive single gene can be completely overcome by regulating the diet of the affected individual..
Phenylketonuria
This results from having defective membrane proteins that normally function in chloride ion transplant...
Cystic fibrosis
Tobacco mosaic virus has RNA rather than DNA as its genetic material..
tobacco mosaic virus
Chemicals from heat-killed S cells were purified. The transforming agent was found to be DNA..
Avery, MacLeod, and McCarty
In any DNA sample, the amount of adenin equals the amount of thymine and the amount of guanine equals the amount of cytosine..
Chargoff
The DNA of a phage was injected into the bacterial host but the protein coat stayed outside.
Hershey and Chase
Concluded that molecules from the dead S cells had genetically transformed living R bacteria into S bacteria..
Griffith
Cytosine makes up 38% of the nucleotides in a sample of DNA from an organism. What percent of the nucleotides in this sample will be thymine?
12
All of the following were determined directly from X-ray diffraction photographs of crystallized DNA except
the sequece of nucleotides
What kind of chemical bonds are found between paired bases of the DNA double helix?
hydrogen
What is the function of DNA polymerase?
to add nucleotides to the end of a growing DNA strand
The strands that make up DNA are anti parallel. This means that..
the 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand
In DNA, the designations 3' and 5' refer to the..
carbon atoms of deoxyribose to which phosphate groups may bond
A new DNA strand only elongates in the 5' to 3' direction because/
DNA polymerase adds nucleotides only to the free 3' end
Which of the following is analogous to telomeres?
the two ends of a shoe lace
A eukaryotic cell lacking telomerase would..
undergo a reduction in chromosome length
DNA and RNA are polymers of..
nucleotides
Which of these is always true with regard to a DNA doube helix?
the amount of adenine is equal to the amount thymine, and the amount of guanine is equal to the amount of cytosine
In his work with pneumonia-causing bacteria and mice, Griffith found that..
some chemical from pathogenic cells was transferred to non pathogenic cells
What is the basis for the difference in the synthesis of the leading and lagging strands of DNA molecules?
DNA polymerase can join new nucleotides only to the 3' end of a growing strand
According to BEadle and Tatum's one gene-one enzyme hypothesis. how many gene's are necessary for this pathway?
2
A mutation results in a defective enzyme a. Which of the following would be a consequence of that mutation?
an accumulation of A and no production of B and C
Which of the following represents a similarity between RNA and DNA?
nucleotides consisting of a phosphate, sugar, and nitrogen base
RNA differs from Dna in that RNA..
both A and C are correct
A possible sequence of nucleotides in DNA that would code for the polypeptide sequnce phe-leu-lie-val would be..
3' AAA-GAA-TAA-CAA 5'
What amino acid sequence will be generated based on the following mRNA codon sequence?
met-ser-ser-leu-ser-leu
What is the sequence of a peptide based on the mRNA sequence 5'UUUUCUUAUUGUCUU?
phe-ser-tyr-cys-leu
A particular eukaryotic protein is 300 amino acids long. Which of the following could be the max # of nucleotides in the DNA that coes for the amino acids in this protein?
900
What are the coding segments of a stretch of eukaryotic DNA called?
exons
Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that includes..
excision of introns
Introns are significant to biological evolution because..
their presence increases the frequency of recombination
A particular triplet of bases in the coding sequence of DNA is AAA. The anticodon on the tRNA that binds the mRNA codon is..
AAA
What is an anticodon part of?
tRNA
The function of the ribosome in polypeptide synthesis is to..
do A, B, and C
As a ribosome translocates along an mRNA molecule by one codon, which of the following occurs?
Both A and C are correct
___________ is the first of three main steps of protein synthesis.
Transcription
______ are deleted portions of an RNA transcript.
Introns
From the behavoir of their mutants, Beadle and Tatum could conclude that..
class I mutants have a nonfunctional enzyme at step A, and class II mutants have a nonfunctional enzyme at step B
The anticodon of a particular tRNA molecule is..
complementary to the corresponding mRNA codon
How many codons are needed to specify three amino acids?
3
The __________ of a tRNA molecule determines the type of amino acid that bonds with the tRNA.
anticodon
What happens during the process of translation?
The cell uses information from messenger RNA to produce proteins
The order of nitrogenous bases in DNA determines the order of __________ in proteins.
amino acids
(T/F) During DNA replication only one strand of DNA serves as a template
false
(T/F)Genes determine a person's eye color by coding for nitogenous bases that affect eye color.
false
(T/F) DNA codes for DNA polymerase
true
(T/F) The anticodon AGA is complementary to the codon TCT
false
Increased UV irradiation causes the skin of humans to become more darkly pigmented. Whe notions that tanned individuals pass these genes onto the children is the idea of..
Jean Baptiste Lamarck
Darwin's mechanism of evolution differed from Lamarck's by proposing that..
inherend variations in the population are more important in evolution than variations acquired during individual lifetimes
Which statement about natural selection is most correct?
Populations change over time as maladapted individuals pass fewer genes on to the next generations
Which statement best describes how the evolution of pesticide resistance occurs in a population of insects?
A # of genetically resistant pesticide survivors reproduce.
If two modern organisms are distantly related in an evolutionary sense, then one should expect that..
they should share fewer homologous organs than two closely related organisms
As adults, certain species of whatles posses baleen instead of teeth. The teeth of embryonic baleen whales are evidence that..
baleen whales are descendants of toothed whales.
Over evolutionary time, many cave-dwellling organisms have lost their eyes. How can natural selection account for these loses?
Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits
What effect fo sexual processes have on the allelic frequencies in a population?
they have no effect on allelic frequencies
In a population that is in Hardy-Weinberg equilibrium, the frequency of the allele is 0.3. What is the percentage of the population that is homozygous for this allele?
9
In a population that is in Hardy-Weinberg equilibrium, the frequency of the allele is 0.3. What is the percentage of the population that is heterozygous for this allele?
42
If the frequency of a particular allele that is present in a small, isolated population of alpine plants should change due to a landslide that leaves an even smaller remnant of surviving plants, then what has occurred?
A and B only (bottleneck, and genetic drift)
In a large, sexually reproducing population, the frequency of an allele changes from 60% to 20%. One can assume..
the allele reduces fitness
Some species of Anopheles mosquito live in brackish water. What type of reproductive barrier is most obviously separating these different species?
habitat isolation
Males of one species sing only during rainy conditions, males of another species sing only when it isn't raining..
behavioral
One species lives only in tree holes; another species lives only in streams..
habitat
Females of one species choose mates based on song quality; others base it on size..
behavioral
One species mates for two weeks in early April; another species mates for 3 weeks in early May..
temporal
Males of one species are too small to perform amplexus with femals of all other species
mechanical
The reproductive barrier that maintains the species boundary between horses and donkeys is..
hybrid sterility
A defining characteristic of allopatric speciation is..
geographic isolation
If the half-life of carbon-14 is about 5,730 years, then a fossil that has 1/8 the normal proportion of carbon 14 is probably _________ years old.
16,800
Active tectonic subduction zones are characterized by..
all of these
Which of the following can best be explained by continental drift?
the scarcity of eutherian mammals in Australia
A major evolutionary episode that corresponded in time most closely with the formation of Pangaea was the..
Permian extinctions
In his labratory simulation of the early earth, Miller observed the abiotic synthesis of..
amino acids