PROKARYOTIC GENE EXPRESSION

Question 1

which genes encode protein invoved in metabolism, biosynthesis or cell structure

Answer 1

Structural genes

Question 2

which genes encode products that interact with other DNA sequences and affect the transcription and translation of these sequences

Answer 2

Regulatory genes

Question 3

DNA sequence that are not transcribed but play a role in regulating sequences to whcih they are physically linked are called

Answer 3

Regulatory element

Question 4

which elements are continuously expressed under normal cellular conditions

Answer 4

Constitutive expression

Question 5

which elements stimulate gene expression

Answer 5

positive regulation

Question 6

which element inhibits gene expression

Answer 6

negative regulation

Question 7

gene expression can be controlled in single or multiple levels

Answer 7

multiple levels

Question 8

what are responsible for binding to DNA by forming hydrogen bonds with DNA

Answer 8

DNA binding domains

Question 9

a short sequence/ structure within the DNA binding domain, that fits into the major groove of DNA is called

Answer 9

Motifs

Question 10

motifs are found on which groove of the DNA

Answer 10

major groove

Question 11

where are helix-turn-helix located

Answer 11

bacterial regulatory protein; related motifs in eukaryotic protein

Question 12

where are zinc finger location

Answer 12

eukaryotic regulatory and other proteins

Question 13

where are steroid receptor located

Answer 13

eukaryotic proteins

Question 14

where would u find leucine zipper motif

Answer 14

in eukaryotic transcription factors

Question 15

where would you find helix-loop-helix

Answer 15

eukaryotic proteins

Question 16

what kind of proteins would u find

Answer 16

homeodomain

Question 17

what control transcription in bacterial cells

Answer 17

operons

Question 18

what are the lac mutations

Answer 18

structural gene mutations
regulatory gene mutations
operator mutations
promoter mutations

Question 19

what does an operon include

Answer 19

promoter+ operator+ structural genes

Question 20

what type of operons is that in which transcription is usually turn off and needs to be turned on

Answer 20

inducible operons

Question 21

what type of operons is that in which transcription is normally on and needs to be turned off

Answer 21

repressible operons

Question 22

small molecule That turns on transcirption is called

Answer 22

inducer

Question 23

What is the effect of negative inducible operons

Answer 23

it inhibits transcription because molecule binds to operator

Question 24

what is the small molecule that binds to the repressor and makes it capable of binding to the operator to turn off transcription

Answer 24

copressor

Question 25

what is the protein that binds to the promoter and thereby increases the efficiency of RNAP binding

Answer 25

Catabolite activator protein (CAP)

Question 26

what is the regulatory protein involved that stimulates transcription by binding to DNA

Answer 26

activator

Question 27

Jacob and Monod deduced that operons interfered with the normal regulation in which organism

Answer 27

E.coli

Question 28

structural genes examples

Answer 28

lacZ, lacY, lacA (ZYA)

Question 29

which encodes B-galactosidase

Answer 29

lac Z

Question 30

which encodes lactose permease

Answer 30

lacY

Question 31

which encodes thiogalactoside transacetylase

Answer 31

lacA

Question 32

what are regulatory genes and sequences

Answer 32

lacI, lacP, lacO (IPO)

Question 33

which encodes lac repressor

Answer 33

lacI

Question 34

does the repression of the lac operon completely shit down transcription

Answer 34

Never Completely

Question 35

Beta-galactosidase converts lactose to

Answer 35

allolactose

Question 36

allolactose converts to

Answer 36

galactose and glucose

Question 37

When lactose is absent from the growth medium, what molecules are produced

Answer 37

B-galactosidase, permease, transacetylase

Question 38

When lactose is added to the medium and glucose is absent, what happens

Answer 38

the rate of synthesis of each enzyme increases about a thousandfold in 2-3 minutes!

Question 39

increase in protein synthesis is driven by

Answer 39

transcription of the lac operon.

Question 40

In the absence of lactose, what happens

Answer 40

the regulator protein (a repressor) binds to the operator and inhibits transcription.

Question 41

which repression favors using glucose when available and repressing the metabolism of other sugars.

Answer 41

Catabolite repression

Question 42

In E. coli, the concentration of cAMP is related to

Answer 42

inversely proportional to the level of available glucose.

Question 43

what is an example of a negative repressible operon

Answer 43

the trp Operon

Question 44

five structural genes in the trp operon

Answer 44

trpE, trpD, trpC, trpB, and trpA

Question 45

the trp operon gene converts

Answer 45

chorismate to tryptophan

Question 46

what affects the continuation of transcription, not its initiation.

Answer 46

Attenuation

Question 47

what is the secondary structure that forms in the 5’ UTR of certain operons that causes the premature termination of transcription.

Answer 47

Attenuator

Question 48

what is the protein or DNA sequence that inhibits the termination of transcription.

Answer 48

Antiterminator

Question 49

what contain binding sites for transcriptional regulators but lie at distance from the gene

Answer 49

Bacterial enhancers

Question 50

what sequence is complementary to targeted partial sequence of mRNA

Answer 50

Antisense RNA

Question 51

what molecules influence the formation of secondary structures in mRNA

Answer 51

Riboswitches

Question 52

what RNA molecules with catalytic activity

Answer 52

Ribozymes

Question 53

when extracellular osmolarity is low,

Answer 53

the ompF mRNA is translated to produce OmpF protein

Question 54

when extracellular osmolarity is high

Answer 54

blocking the ribosome-binidng site and synthesis of the OmpF protein is reduced.