Test 3

Question 1

Topoisomerase

Answer 1

breaks, swivels, and rejoins strands ahead of the fork to relieve the strain from overwind

Question 2

Helicase

Answer 2

untwists the double helix at the replication forks.

Question 3

primase

Answer 3

joinds RNA nucleotides together at the origin

Question 4

DNA ligase

Answer 4

joins the okazaki fragments forming a simple single new DNA strand

Question 5

DNA Polymerase I

Answer 5

replaces RNA primers with DNA

Question 6

DNA polymerase III

Answer 6

forms a new DNA strand during replication by adding nucleotides.

Question 7

Okasaki fragment

Answer 7

small fragments of about 1000 bases that are joined after synthesis to form the lagging strand

Question 8

leading strand

Answer 8

elongates continuously in the 5-3 direction

Question 9

lagging strand

Answer 9

Okasaki fragments joined together in the 3-5 prime directoin

Question 10

single strand binding proteins

Answer 10

stabilizes the DNA strand just after the fork until it can serve as template

Question 11

Bacteriophage

Answer 11

a virus for which the natural host is a bacterial cell. literally bacteria eaters

Question 12

Nucleoside

Answer 12

ribose and nucleotides

Question 13

DNA

Answer 13

deoxyribose and nucleotide

Question 14

RNA

Answer 14

Ribose and nucleotide

Question 15

Purines

Answer 15

Adenine and Guanene

Question 16

Pyrimidines

Answer 16

Cytosine and thymine

Question 17

bonds between base pairs

Answer 17

hydrodene bonds

Question 18

bonds linking nucleotides

Answer 18

covalent bond

Question 19

direction of making a new strand

Answer 19

towards the 3”

Question 20

polarity

Answer 20

an overall direction

Question 21

terminalization

Answer 21

shifting of the chiasmata from the original position at the centromere toward the chromosome end or telomere.

Question 22

telomeres

Answer 22

maintenace and accurage replication of the ends of a crhomosome

Question 23

Hershey and chase experiment

Answer 23

Helped prove DNA was genetic material. bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters the host bacterial cell, but most of the protein doesnt.

Question 24

heteroduplex

Answer 24

often formed as intermediates during crossing over. two strands have nonidentical sequences.

Question 25

complementation

Answer 25

2 blind parents make child that can see becuase both are heterozygous and dominant on either one.

Question 26

deletion

Answer 26

block of 1 or more base pairs is lost

Question 27

forward mutation

Answer 27

changes wild type allele to a different allele

Question 28

deamination

Answer 28

removal of amino group from regular DNA

Question 29

reciprical translocation

Answer 29

parts of two nonhomologous chromosomes change places

Question 30

transposable elements TEs

Answer 30

jump around the genome and dirupt its function.

Question 31

Alkyltransferase

Answer 31

removes alkyl groups

Question 32

Mutation

Answer 32

A heritable change in the DNA

Question 33

tautomers

Answer 33

interconversion of bases between two similar forms

Question 34

wild type

Answer 34

found on majority of chromosomes in population

Question 35

intercalating agents

Answer 35

sandwich themselves between successive base pairs and disrupt

Question 36

transversion

Answer 36

substitution mutation when a purine replaces a pyrimidine or oposite

Question 37

trasnsition

Answer 37

substitution mutation when one purine replaces another purine. or one pyrimidine replaces another pyrimidine

Question 38

somatic mutation

Answer 38

regular cells pass down a mutation that can cause cancer

Question 39

germ line mutation

Answer 39

sex cells pass down muation that cause natural selection

Question 40

Base analogs

Answer 40

replace a base, almost identical to normal base

Question 41

X ray

Answer 41

causes increase in muttion rate

Question 42

deamination agent

Answer 42

removes amino group from DNA

Question 43

Alkylating agents

Answer 43

add ethyl or methyl groups

Question 44

Hydroxylating agents

Answer 44

add an OH group

Question 45

what does unequal crossing over cause

Answer 45

deletion on one homolog and a duplication on the other homolog

Question 46

Fluctuation experiment with Luria and Delbruck

Answer 46

infected wild type bacteria with phage. Preexisting resistance to chemicals.

Question 47

permutation

Answer 47

arranging the order of elements

Question 48

Unstable nucleotide repeats cause

Answer 48

Fragile x syndrome and huntingtons disease

Question 49

Fragile X Syndrome

Answer 49

2nd to downs in causing mental retardation

Question 50

SOS system

Answer 50

used at replication forks that stalled becuase of unrepaired DNA damage. Adds random nucleotides opposite damaged bases.

Question 51

Nonhomolougous end joining

Answer 51

a pathway that reparis double stranded breaks in DNA

Question 52

Nucleotide excision repair

Answer 52

corrects damaged nucleotides

Question 53

Avery, McCleod, McCarty experiment

Answer 53

Suggested that DNA was genetic holder rather than protein

Question 54

Chargaff expermiment

Answer 54

found the base pairs

Question 55

Griffith experiment

Answer 55

Transformation with baterica genetic material

Question 56

Watson and Crick experiment

Answer 56

described the structure of DNA

Question 57

photolyase

Answer 57

seperation of molecules by light

Question 58

Rhodopsin genes

Answer 58

vision in the dark

Question 59

complementation testing

Answer 59

reveals whether two mutations are in a single gene or in different genes