Gene Control

Question 1

start codon

Answer 1

AUG

Question 2

stop codon

Answer 2

UAA, UAG, UGA

Question 3

ncRNA

Answer 3

functions like a protein without being translated into protein

ex. tRNA, rRNA (used to translate mRNA into protein)

Question 4

EPA

Answer 4

E- exit
P - polypeptide grows here
A - where new tRNA lands

Question 5

poly-A tail

Answer 5

in eukaryotes, polyadenylation is the addition of poly(A) tail to the 3’ end of messenger RNA

consists of multiple adenosine phosphates

Question 6

guanine cap

Answer 6

in eukaryotes, a 5-prime cap is added to mRNA

Question 7

5’-3’ exonuclease activity

Answer 7

5-3 removes in the opposite direction in which DNA is formed

Question 8

DNA pol 1

Answer 8

5-3’ exonuclease activity

also: used in prokaryotic DNA replication

Question 9

mismatch repair mechanism

Answer 9

protein marks with a cut, exonuclease removes nucleotide, DNA pol, DNA ligase

Question 10

methylated parent strand*

Answer 10

found in prokaryotes

Question 11

exogenous DNA damage caused by…

Answer 11

1. UV rays
2. gamma rays
3. X-rays

“UVGX”

Question 12

co-translation protein modification*

Answer 12

acetylation of a polypeptide

Question 13

post-translational modification

Answer 13

lycosylation - addition of a carb to protein on the surface of a lipid membrane; helps with identification of different kinds of cells (ABO blood types)

occurs in ER and GA

Question 14

lipidation

Answer 14

adding lipid to a protein that anchors a protein to a cell membrane

“lipidation makes proteins soluble in membranes”

Question 15

ubiquitination

Answer 15

marks a protein for degradation, various parts are recycled

“ubiquitous parts for degradation”

Question 16

jacob monod lac operon

Answer 16

when lactose is present, binds to the repressor protein and lets go of operator, allowing mRNA to be produced

when lactose is low, lactose comes off the repressor, and the repressor binds to the operator site

Question 17

lac operon

Answer 17

contains genes necessary to enhance lactose metabolism

Question 18

cleavage of lactose*

Answer 18

carried out by beta-galactosidase encoded for by lacZ, not by lactose permease

Question 19

deacetylation of histones*

Answer 19

coils (hides) the histone structure

• preventing it from being accessed by the transcriptional machinery

deacetylation = hiding

Question 20

CpG methylation*

Answer 20

silences (or turns off) DNA once its has differentiated, diminishes oncogenic potential of cells

Question 21

DNA pol III

Answer 21

detects errors and fix the DNA

Question 22

allolactose

Answer 22

a disaccharide similar to lactose; an inducer of the lac operon

• engenders a conformational change in the repressor protein, causing it to dissociate from the lac operon, allowing for transcription of lac operon to occur