Final Terms Part 2

Question 1

Okazaki fragment

Answer 1

fragments in the lagging strand

Question 2

heliase

Answer 2

breaks the hydrogen bonds between base pairs to unzip DNA

Question 3

SSB protein

Answer 3

prevents strands from reannealing

Question 4

primase

Answer 4

lays down a short RNA primer

Question 5

DNA polymerase

Answer 5

adds complementary base pairs starting off a primer

Question 6

ligase

Answer 6

seals the backbone nick between adjacent framents

Question 7

topoisomerase

Answer 7

alter the supercoiling by nicking the backbone

Question 8

transcription

Answer 8

DNA->RNA

Question 9

template strand

Answer 9

strand that is transcribed

Question 10

coding strand

Answer 10

strand that is not transcribed - code will look like RNA’s

Question 11

consensus sequence

Answer 11

genetic sequence found with minor variations and similar functions in widely diverse organisms

Question 12

centromeres

Answer 12

constitive heterochromatin

from a constrictive region on chromosomes mitotic spindle fibers attach to these

Question 13

telomeres

Answer 13

tandemly repeated DNA at the ends of linear chromosomes

protects the ends of chromosome from exonucleases

Question 14

exons

Answer 14

expressed

transcribed and often translated

Question 15

introns

Answer 15

transcribed but not translated -removed

Question 16

5’ capping

Answer 16

protects RNA from exonucleases because they can’t cut 5’-5’

necessary for correct position of ribosome during translation

Question 17

polyadenylation

Answer 17

mRNA is cleaved at a polyA site to terminate transcription
50-250 adenine nts added to the 3’ end by polyA polymerase
protection from 3’ to 5’ exonucleases
part of gene expression regulation

Question 18

gene regulatory elements

Answer 18

occurs throughout the central dogma
gives cell specialized role
gene product dosage
nuclear exprot from envelope
response to change in environment
development stages

Question 19

enhancer

Answer 19

DNA sequence that is bound by activators to increase transcription of gene

Question 20

activators

Answer 20

protein that binds to enhancers

have 2 domains: DNA building domain and transcription activation domain

Question 21

repressors

Answer 21

proteins that bind silencers

Question 22

silencers

Answer 22

DNA sequence that is bound by repressors to decrease transcription of gene

Question 23

mRNA splicing

Answer 23

removal of introns by spliceosome

Question 24

alternative splicing

Answer 24

some RNA is spliced differently to produce a different protein

Question 25

spliceosome

Answer 25

performs the removal of introns

Question 26

rRNA

Answer 26

ribosomal RNA - component in ribosome

Question 27

snRNA

Answer 27

small nuclear RNA- usually involved in splicing

Question 28

translation

Answer 28

RNA to protein

Question 29

polypeptide

Answer 29

chain of amino acids

Question 30

protein

Answer 30

polypeptide that is folded to perform a function

Question 31

amino acids

Answer 31

composed of -NH2 and -COOH
make up polypeptides
each have unique features governed by R group

Question 32

codon

Answer 32

3 bp sequence that codes for an amino acid