Exam 5

Question 1

describe the process of transcription

Answer 1

info from dna sequence is transcribed to rna

components: initiation, elongation, and termination

Question 2

what is initiation in prokaryotes

Answer 2

sigma factor binds to promoter, transcription factors bind for initiation.

Question 3

what is initiation in eukaryotes

Answer 3

transcription factors recognize promoter, RNA polymerase II binds, form transcription initiation complex

Question 4

what is translation

Answer 4

ribosomes read info from mrna to make amino acid chain (polypeptide)

Question 5

what bonds are between polypeptides

Answer 5

peptide bonds

Question 6

describe mRNA structure and role

Answer 6

nucleotide sequence that translates to amino acid sequence by the use of ribosome

Question 7

what does rRNA do

Answer 7

make up ribosomes

Question 8

what does tRNA do

Answer 8

carries amino acid and base pairs with mRNA

Question 9

describe the P site of ribosome

Answer 9

first subunit of tRNA binds

Question 10

describe A site of ribosome

Answer 10

2nd codon of tRNA enters ribsomes A site

Question 11

describe E site of ribosome

Answer 11

tRNA exits

Question 12

What happens in elongation of transcription

Answer 12

RNA polymerase moves along template and is synthesised 5’-3’

Question 13

what happens in termination in transcription in prokaryotes

Answer 13

mRNA strand released and read by ribosome

Question 14

what happens in termination in transcription in eukaryotes

Answer 14

pre-mRNA spliced into mature mRNA

Question 15

what happens in splicing?

Answer 15

introns are removed, only exons

this is also called RNA processing

Question 16

what does the 5’ cap do in termination

Answer 16

facilitates translation initian and prevent degradation of mRNA

Question 17

what does the poly A tail do in termination in transcription

Answer 17

stabilizes mRNA export and prevents degradation

Question 18

name the start codon

Answer 18

AUG

Question 19

name the 3 stop codons

Answer 19

UAA UAG UGA

Question 20

describe translation

Answer 20

initiation, elongation, termination

non-ambiguous

degenerate(

Question 21

describe degeneracy in translation

Answer 21

each sequence only codes for 1 type of amino acid

Question 22

what happens during initiation of translation

Answer 22

ribosomes attach to mRNA by tRNA

Question 23

what happens during elongation of translation

Answer 23

Remaining goes to A site

Question 24

what happens in termination of tranlation

Answer 24

stop codon goes to A site, complex removes in E site, amino acid chain is free

Question 25

how many promoters do eukaryotes have

Answer 25

multiple

Question 26

how many promoters do prokaryotes have

Answer 26

1

Question 27

how many gene regulators do eukaryotes have

Answer 27

1

Question 28

how many gene regulators do prokaryotes have

Answer 28

multipel

Question 29

what transcription factor positively regulates transcription

Answer 29

lac operon

Question 30

which transcription factor negatively regulates transcription

Answer 30

trp

Question 31

how many structural genes are in the lac operon

Answer 31

3

Question 32

name the structural genes in the lac operon

Answer 32

lac Z, lac Y, and lac A

Question 33

what does lac Z do

Answer 33

code for betagalactosidase, hydrolyzes lactose in galactose and glucose

Question 34

what does lac Y do

Answer 34

codes for beta galactosides, moves lactose in to cell

Question 35

what does lac A do

Answer 35

transforms actyl group into beta galactoside

Question 36

what does lac I do

Answer 36

code for repgressor gene

Question 37

is the lac operon usually off or on

Answer 37

off

Question 38

is the lac operon catabolic or anabolic

Answer 38

catabolic

Question 39

is the lac operon inducible or repressible, why?

Answer 39

indicuible because it's usually turned off

Question 40

what does the lac operon do

Answer 40

break down lactose

Question 41

what does the trp operon do

Answer 41

make tryptophan

Question 42

is the trp operon usually off or on

Answer 42

on

Question 43

is the trp operon catabolic or anabolic

Answer 43

anabolic

Question 44

what is epigenetic control

Answer 44

regulates access to eukaryotic genes

Question 44

is the trp operon repressible or inducible, why?

Answer 44

repressible bc its usually on

Question 45

what do acetyl groups do for histones?

Answer 45

bind to the tail, allow DNA to be transcibable

Question 46

what is euchromatin

Answer 46

transcribable histone proteins, loose

Question 47

what is heterochromatin

Answer 47

intranscribable DNA, condensed, dark

Question 48

what is alternative splicing

Answer 48

different exon combos

Question 49

what is mRNA degraded by

Answer 49

microRNA

Question 50

how are proteins degraded

Answer 50

proteosomes

Question 51

what does molecular cloning produce

Answer 51

recombinant DNA

Question 52

how does molecular cloning work

Answer 52

DNA insterted into plasma vector into a bacteria

Question 53

what is in a plasma vector

Answer 53

-orgin of replication -selectable marker -restriction site for cloning

Question 54

what are expression vectors used for

Answer 54

used to increases transgenes protein product

Question 55

how does gene therapy work

Answer 55

vector used to deliver a gene to treat, prevent, or cure a disease