Biology Test 2

Front 1

the impact of a single gene on more than one characteristic

Back 1

pleiotropy

Front 2

a molecule carrying DNA from more than one source

Back 2

recombinant DNA (transgenic organism)

Front 3

States that genes are located on chromosomes and that the behavior of chromosomes during meiosis and fertilization accounts for inheritance patterns.

Back 3

chromosome theory of inheritance

Front 4

the enzymes that make the covalent bonds between the nucleotides of a new DNA strand

Back 4

DNA polymerases

Front 5

the transfer of genetic info from DNA into an RNA molecule

Back 5

transcription

Front 6

the transfer of genetic info in the RNA into a protein

Back 6

translation

Front 7

small, circular DNA molecules that are separate from the much larger bacterial chromosome

Back 7

bacterial plasmids

Front 8

DNA carriers that move genes from one cell to another

Back 8

vectors

Front 9

a technique by which any segment of DNA can be amplified (cloned)

Back 9

polymerase chain reaction (PCR)

Front 10

a method for sorting macromolecules - proteins or nucleic acids - primarily on the basis of their electrical charge and length

Back 10

gel electrophoresis

Front 11

human chromosomes contain how many genes?

Back 11

3.2 billion nucleotide pairs of DNA and 30,000 to 40,000 genes

Front 12

Fertilization of one plant by pollen from a different plant

Back 12

cross-fertilization

Front 13

varieties for which self-fertilization produced offspring all identical to the parent

Back 13

true-breeds

Front 14

the offspring of two different true-breeding varieties

Back 14

hybrids

Front 15

pairs of alleles segregate (separate) during gamete formation; the fusion of gametes at fertilization creates allele pairs again

Back 15

Mendel's principle of segregation

Front 16

when an orgaism has a pair of identical alleles for a gene

Back 16

homozygous

Front 17

when an organism has two different alleles for a gene

Back 17

heterozygous

Front 18

each pair of alleles segregates independently of the other pairs during gamete formation

Back 18

Mendel's principle of independent assortment

Front 19

chromosomes other than the sex chromosomes

Back 19

autosomes

Front 20

hybrids that have an appearance in between the phenotypes of the two parents

Back 20

incomplete dominance

Front 21

How does codominance differ from incomplete dominance?

Back 21

codominance is the expression of both alleles; incomplete dominance the expression of one intermediate trait

Front 22

The DNA-containing structures that carry the organism's genes.

Back 22

chromosomes

Front 23

A complete set of an organism's genes. (Humans have around 35,000 genes.) Located on chromosomes in the cell nucleus.

Back 23

genome

Front 24

A combination of DNA and protein molecules.

Back 24

chromatin

Front 25

Consists of DNA wound around a protein core of eight histone molecules.

Back 25

nucleosome

Front 26

Each chromosome consists of two copies of these before beginning division.

Back 26

sister chromatids

Front 27

A typical body cell, has 46 chromosomes in humans.

Back 27

somatic cell

Front 28

The two chromosomes of a matching pair.

Back 28

homologous chromosomes

Front 29

All body cells in an organism contain two homologous sets of chromosomes.

Back 29

diploid organism

Front 30

A cell with a single chromosome set.

Back 30

haploid cell

Front 31

egg and sperm cells

Back 31

gametes

Front 32

An exchange of genetic material - pieces of chromosomes - between homologous chromosomes, occurs during the first prophase of meiosis.

Back 32

crossing over

Front 33

These chromosome are called _______ because they result from genetic recombination, the production of gene combinations different from those carried by the parental chromosomes.

Back 33

recombinant (chromosomes)

Front 34

trisomy 21

Back 34

Down's syndrome

Front 35

The members of a chromosome pair fail to separate at anaphase.

Back 35

nondisjunction

Front 36

XXY

Back 36

Klinefelter syndrome (male)

Front 37

XO

Back 37

Turner syndrome (female)

Front 38

Organism that has more than two sets of homologous chromosomes in each somatic cell.

Back 38

polyploid

Front 39

the organs that produce gametes

Back 39

gonads

Front 40

Cells with the potential to give rise to every type of cell in the body.

Back 40

stem cells

Front 41

In "The Origin of Species," (1859) Charles Darwin proposed that:

Back 41

1. Modern species descended from ancestral species (descent with modification) and 2. natural selection is the mechanism of evolution.

Front 42

The idea that a population of organisms can change over the generations if individuals having certain heritable traits leave more offspring than other individuals.

Back 42

natural selection

Front 43

How old is the earth?

Back 43

3.5 billion years old

Front 44

The comparison of body structures between different species.

Back 44

comparative anatomy

Front 45

similarity due to common ancestry

Back 45

homology

Front 46

the comparison of structures that appear during the development of different organisms

Back 46

comparative embryology

Front 47

consists of all alleles in all the individuals making ap a population

Back 47

gene pool

Front 48

What produces genetic variation?

Back 48

mutations and sexual recombination

Front 49

a general formula for calculating the frequencies of genotypes in a gene pool from the frequencies of alleles, and vice versa

Back 49

Hardy-Weinberg formula

Front 50

A nonevolving population is in genetic equilibrium, also called

Back 50

Hardy-Weinberg equilibrium

Front 51

Evolution is a generation-to-generation change in a population's frequencies of alleles. Because this describes evolution on the smallest scale, it is sometimes referred to as ______

Back 51

microevolution

Front 52

a change in the gene pool of a small population due to chance

Back 52

genetic drift

Front 53

Genetic drift due to a drastic reduction in population size

Back 53

the bottleneck effect

Front 54

Genetic drift occurs when a few individuals colonize a new habitat. The smaller the colony, he less its genetic makeup will prepresent the gene pool of the larger population from which the colonists emigrated. Genetic drift in a new colony is called _____

Back 54

the founder effect

Front 55

Apopulation may gain or lose alleles by ____, or genetic exchange between two populations

Back 55

gene flow

Front 56

the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals

Back 56

Darwinian fitness

Front 57

a change in life-forms noticeable enough to be evident in the fossil record

Back 57

macroevolution

Front 58

a population or group of populations whose members have the potential to interbreed with one another in nature to produce fertile offspring

Back 58

species

Front 59

the origen of new species

Back 59

speciation

Front 60

domain > kingdom > phylum > class > order > family > genus > species

Back 60

taxonomic hierarchy

Front 61

both DNA and RNA are nucleic acids which consist of long chains (polymers) of units called

Back 61

nucleotides

Front 62

DNA and RNA nucleotides are joined by covalent bonds between the sugar of one nucleotide and the phosphate of the next. What is this called?

Back 62

sugar-phosphate backbone

Front 63

Each nucleotide of DNA or RNA consists of what three components?

Back 63

a nitrogenous base, a sugar (deoxyribose, ribose), and a phosphate group

Front 64

two polynucleotide strands of DNA

Back 64

double helix

Front 65

The genetic instructions for the amino acid sequence of a polypeptide chain are written in DNA and RNA as a series of three-base words called

Back 65

codons

Front 66

RNA nucleotides are linked by the transcription enzyme called

Back 66

RNA polymerase

Front 67

The nucleotide sequence that says "start transcribing" that the RNA polymerase attaches to is called

Back 67

a promoter

Front 68

Phase 1 of transcription; the attachment of RNA polymerase to the promoter and the start of RNA synthesis is called

Back 68

initiation

Front 69

phase 2 of transcription; the RNA grows longer and peels away from its DNA template, allowing the two separated DNA strands to come back together in the region already transcribed

Back 69

elongation

Front 70

phase 3 of transcription; the RNA polymerase reaches a special sequence of bases in the DNA template called a terminator.

Back 70

termination

Front 71

the sequence of bases in the DNA template that signals the end of transcription

Back 71

terminator

Front 72

RNA translation yields

Back 72

a polypeptide of amino acids

Front 73

what are the two types of mutations?

Back 73

base substitutions and base insertions or deletions

Front 74

Viruses that attack bacteria are called

Back 74

bacteriophages, or phages

Front 75

A reproduction cycle of a virus that uses the cell's machinery to produce copies of the virus. The cell lyses, or breaks open.

Back 75

lytic cycle

Front 76

A virus cycle; the virus DNA inserts by genetic recombination into the bacterium's DNA. The prophage DNA replicates along with the host cell DNA.

Back 76

lysogenic cycle

Front 77

Once inserted into the bacterial chromosome, the phage (virus) DNA is called a

Back 77

prophage

Front 78

The synthesis of DNA on an RNA template

Back 78

reverse transcriptase