Genes

Question 1

Nucleotide: monomer

Answer 1

A sugar (deoxyribose) with a phosphate group attached to it and a base

Question 2

Deoxyribose bases

Answer 2

Adenine (A), Guanine (G), Cytosine (C), or Thymine (T)

Question 3

Protein: polypeptide

Answer 3

Long chain of 20 types of amino acids, each linked by a covalent peptide bond

Question 4

Protein: pH 7

Answer 4

Both the amino and carboxyl groups are ionized

Question 5

optical isomers

Answer 5

Proteins consist of exclusively L amino acids

Question 6

Lysine side chain

Answer 6

Basic NH3+ amide group

Question 7

Arginine side chain

Answer 7

Basic NH2+ resonance

Question 8

Histidine side chain

Answer 8

Basic NH+ weak pentagon

Question 9

Deoxyribose sugar

Answer 9

H at the 2’ carbon position

Question 10

Ribose sugar

Answer 10

OH at the 2’ carbon position

Question 11

Purine bases

Answer 11

Adenine and Guanine with double rings

Question 12

Pyrimidine bases

Answer 12

Thymine, Cytosine and Uracil with single rings

Question 13

Nucleoside

Answer 13

A base attached to only a sugar: adenine+ribose–>adenosine

Question 14

Adenosine triphosphate

Answer 14

ATP nucleotide containing adenine, ribose, and three phosphate groups

Question 15

Guanosine triphosphate

Answer 15

GTP nucleotide containing guanine, ribose, and three phosphate groups

Question 16

deoxyadenosine triphosphate

Answer 16

dATP nucelotide containing adenine, deoxyribose, and three phosphate groups

Question 17

phosphodiester bond

Answer 17

two covalent phosphoester bonds with phosphate attached to 5’ carbon of one sugar and 3’carbon of another sugar

Question 18

Chargaff’s rule

Answer 18

Equal amounts of A&T, G&C. A+G=T+C

Question 19

DNA directionality

Answer 19

Phosphate group adds on to 3’ hydroxyl end

Question 20

Complete helix turn

Answer 20

One helix turn is 3.4 nm and contains 10 nucleotides

Question 21

Bases: hydrogen bonds

Answer 21

G and C -> 3 bonds. A and T -> 2 bonds

Question 22

A DNA

Answer 22

Right handed helix and tilted on axis

Question 23

B DNA

Answer 23

Predominant DNA in living cells, right handed helix

Question 24

Z DNA

Answer 24

Left handed helix, may affect transcription and level of chromosome compaction

Question 25

RNA helix

Answer 25

RNA can be single stranded or be double stranded at some points

Question 26

Structural gene

Answer 26

Nucleotide sequences that encode proteins

Question 27

Intergenic regions

Answer 27

nontranscribed regions of DNA located between adjacent genes

Question 28

DNA gyrase

Answer 28

In bacteria travels in front of DNA helicase and relaxes positive supercoils

Question 29

Topoisomerase I

Answer 29

In bacteria relaxes negative supercoils

Question 30

Quinoline + coumarin

Answer 30

Drugs that inhibit gyrase and bacterial topoisomerases but not eukaryotic topoisomerase

Question 31

Chromatin

Answer 31

DNA-protein complex found within eukaryotic chromosomes

Question 32

Centromere

Answer 32

Recognition site for kinetochore proteins during mitosis and meiosis

Question 33

Eukaryotic origin of replication

Answer 33

each chromosome contains OR every 100,00 bp

Question 34

Eukaryotic Chromosome bp

Answer 34

Tens of millions to hundreds of millions bp

Question 35

Telomeres

Answer 35

inhibit chromosomal rearrangements such as translocations

Question 36

Nucleosome

Answer 36

double stranded segment of DNA wrapped around octamer of histone proteins

Question 37

DNA:nucleosome

Answer 37

150 bp around histones + 20-100 bp linker region

Question 38

Interphase compaction

Answer 38

Nucleosomes+zigzag 30 nm fiber+radial loops

Question 39

Radial loops

Answer 39

Chromosome sequences matrix attachment regions attaching to nuclear matrix

Question 40

Euchromatin

Answer 40

capable of gene transcription and forms radial loop domains during interphase

Question 41

heterochromatin

Answer 41

compacted regions at centromere and telomere

Question 42

Facultative heterochromatin

Answer 42

chromatin that can occasionally interconvert between heterochromatin and euchromatin

Question 43

histone code hypothesis

Answer 43

Patterns involving phosphorylation of serine at first position in H2A and acetylation of 5th and 8th lysine in H4 may attract chromatin loosening proteins

Question 44

Condensin

Answer 44

Enters nucleus at M phase and converts euchromatin in chromatids to heterochromatin

Question 45

cohesin

Answer 45

promotes binding between sister chromatids after s phase through prophase along entire length

Question 46

Separase

Answer 46

cohesins at centromere remain attached until anaphase

Question 47

Semiconservative model

Answer 47

14N and 15N radioiosyptes showed DNA replication

Question 48

bacteria ori

Answer 48

DnaA binds to ori and recriuts DNA helicase

Question 49

DNA helicase

Answer 49

when this enzyme encounters double stranded regions it breaks the hydrogen bonds between the strands to generate single strands

Question 50

Single strand binding proteins

Answer 50

binds to single DNA strands and prevents double helix

Question 51

DNA primase

Answer 51

synthesizes short strands of RNA called RNA primers

Question 52

okazaki fragment

Answer 52

1,000-2,000 fragments in length

Question 53

DNA polymerase III fidelity

Answer 53

1 mistake in 100 million nucleotides

Question 54

oriC regulation

Answer 54

DnaA protein amount and GATC methylation sites in oirigin

Question 55

Eukaryotic origins

Answer 55

replication proceeds bidirectionally from many origins during S phase

Question 56

ARS elements

Answer 56

50 bp and necessary to initiate chromosome replication

Question 57

DNA polymerase y(gamma)

Answer 57

replication of mitochondria DNA

Question 58

DNA polymerase a(alpha)

Answer 58

associates with primase to synthesize RNA primers followed by 20 DNA bp

Question 59

DNA polymerase delta

Answer 59

possible greater role in lagging strand synthesis

Question 60

DNA polymerase e(epsilon)

Answer 60

possible greater role in leading strand synthesis

Question 61

telomerase

Answer 61

synthesizes additional repeats of telomeric sequences

Question 62

homologous chromosomes

Answer 62

homologs - the maternal and paternal chromosomes of a pair