genetics exam 4

Question 1

mutation where a single base pair is changed

Answer 1

point mutation

Question 2

mutation where a large portion of chromosomes are affected

Answer 2

large scale mutation

Question 3

mutation where pyrimidine ->pyrimidine or purine->purine

Answer 3

transitions

Question 4

mutation where purine ->pyrimidine or vice versa

Answer 4

transversion

Question 5

change in a reproductive cell, like an egg or sperm

Answer 5

germ line

Question 6

a change in DNA that happens in any cell except reproductive cells

Answer 6

somatic

Question 7

change in base produces same amino acid as before

Answer 7

silent mutations

Question 8

a change in a gene’s DNA that replaces an amino acid with a different one

Answer 8

missense mutation

Question 9

insertions and deletions, not multiple of 3 bases; DNA sequence is inserted or deleted by a number of nucleotides; shifts entire genome

Answer 9

frameshift mutation

Question 10

the result is a shift of all genetic material because one base is added or removed, altering the entire genome

Answer 10

insertions or deletions

Question 11

base change initiated a premature stop codon

Answer 11

nonsense mutation

Question 12

mutations that occur naturally

Answer 12

spontaneous

Question 13

mutations that are caused by exposure to external factors

Answer 13

induced

Question 14

anything that induces a higher rate of mutation than the spontaneous rate of mutation

Answer 14

mutagen

Question 15

mutagens such as x-rays, gamma rays, UV light

Answer 15

radiation

Question 16

mutagen such as base analogs or intercalating agents

Answer 16

chemicals

Question 17

mutagen such as viruses or bacteria

Answer 17

biological agents

Question 18

mutations can be induced to identify genes that are involved in particular processes (ex: stickleback fish)

Answer 18

genetic dissection

Question 19

molecular basis for spontaneous mutations here nitrogenous bases pair with atypical bases

Answer 19

tautomers

Question 20

molecular bases for spontaneous mutations due to the splitting of repetitive DNA during replications

Answer 20

streisinger model for duplications and deletions

Question 21

loss of purine base from DNA strand

Answer 21

depurination

Question 22

conversion of cytosine to uracil

Answer 22

deamination

Question 23

molecular basis for induced mutations where ____ can pair with different bases depending on their chemical form

Answer 23

base analogs

Question 24

molecular bases for induced mutations where ___ insert between adjacent bases and distort the structure of DNA

Answer 24

intercalating agents

Question 25

induces pyrimidine dimers (covalent bonds between adjacent Ts)

Answer 25

UV light

Question 26

produces highly reactive oxygen species that chemically alter DNA bases

Answer 26

ionizing radiation

Question 27

what results from the disruption of the normal balance between cell proliferation and cell death and is essentially a disease of cell numbers

Answer 27

cancer

Question 28

___ act as regulatory subunits that bind to and activate cyclin-dependent kinases, which then phosphorylate specific target proteins at different stages of the cell cycle, triggering the necessary transition between G1 to S or G2 to M

Answer 28

cyclin

Question 29

___ activates the cyclin-dependent Rb protein, allowing for the transcription of genes necessary for DNA replication to proceed

Answer 29

Cyclin E pathway

Question 30

how ___ stimulates cell proliferation; binds to its specific receptor on the cell membrane, which triggers a cascade of genes involved in cell division

Answer 30

insulin-like growth factor (IGF-I)

Question 31

key step in initiating cell cycle progression; induces genes in the mitogen-activated protein kinase pathway

Answer 31

activation of intracellular signaling

Question 32

programmed cell death, a cell self-destructs as part of normal biological function

Answer 32

apoptosis

Question 33

1) increasing the activity of a growth-promoting protein 2) causing the protein to be produced in abnormally high quantities

Answer 33

mutations in oncogenes

Question 34

recombination occurs during ___ where homologous chromosomes pair up and exchange genetic material through a process called crossing over

Answer 34

prophase I

Question 35

inversions and translocations

Answer 35

chromosome rearrangements

Question 36

deletions and duplications

Answer 36

nitrogenous base variations

Question 37

genetic process where DNA strands can break at random locations on a chromosome, the broken pieces can then rejoin with segments from another chromosome

Answer 37

chromosomal translocation

Question 38

crossover between repetitive DNA sequences that are found at different sited throughout the genome

Answer 38

unequal crossover

Question 39

when 2 different chromosomes exchange pieces of genetic material with each other

Answer 39

reciprocal translocations

Question 40

when the entire long arms of two acrocentric chromosomes fuse together, creating a single large chromosome

Answer 40

Robertsonian translocations

Question 41

variation in the number of complete sets of chromosomes; monoploid, haploid, diploid, and polyploids

Answer 41

euploidy

Question 42

individuals who do not have complete sets of chromosomes (missing or extra); nullisomic, monosomic, trisomic

Answer 42

aneuploidy

Question 43

turner syndrome, klinefelter syndrome, downs syndrome, and Edwards syndrome

Answer 43

human aneuploids

Question 44

study of genetic variation in populations and factors that cause changes in genetic variation

Answer 44

population genetics

Question 45

___ is a measure of genetic variation in individuals and populations

Answer 45

heterozygosity

Question 46

HW equilibrium applies when certain conditions are met;

Answer 46

large population size, random mating, no mutation, no migration, discrete generations, no selection

Question 47

how ___ can change alleles and genotype frequencies by favoring individuals with certain advantageous alleles, allowing them to survive and reproduce more successfully

Answer 47

natural selection

Question 48

conditions required for microevolution by natural selection

Answer 48

variation within a population, heritable traits, differential reproduction, time for traits to become prevalent