lecture 7

Question 1

regulatory genes are genes whose products made of what. do what?

Answer 1

RNA or Protein. Dna sequences of other structural genes and affect their transcription or translation

Question 2

regulatory elements

Answer 2

DNA sequences, where the proteins produced by regulatory genes recognize and bind

Question 3

which control stimulates?

Answer 3

positiv

Question 4

which control inhibits?

Answer 4

negative

Question 5

DNA binding proteins

Answer 5

affect gene expression at transcription level

Question 6

domains in DNA binding proteins are responsible for what?

Answer 6

bind to the DNA

Question 7

3 types of types of binding proteins?

Answer 7

zinc finger, helix turn helix, leucine zipper

Question 8

regulatory genes encode what?

Answer 8

regulatory proteins

Question 9

what initiates the structural gene expression?

Answer 9

promoter

Question 10

operator is bound by what and does what?

Answer 10

regulatory protein. regulate transcription

Question 11

structural genes encode what

Answer 11

functional proteins

Question 12

operon is recognized by what?

Answer 12

regulator protein

Question 13

the operator is located where?

Answer 13

between the promoter and structural genes

Question 14

regulator protein of negative is what?

Answer 14

repressor

Question 15

regulator protein of positive is what?

Answer 15

activator

Question 16

inducible operon transcription is normally ..

Answer 16

off

Question 17

repressible operon transcription is normally

Answer 17

on

Question 18

in negative inducible operon usually there is what?

Answer 18

a repressor attached to operator that prevents transcirption

Question 19

what is needed to in negative inducible?

Answer 19

a inducer

Question 20

what does the inducer bind to?

Answer 20

regulatory protein and prevents it from binding to the operator

Question 21

which operon has a active regulator protein?

Answer 21

negative inducible

Question 22

which operon has an inactive regulator protein?

Answer 22

negative repressible

Question 23

what is needed in negative repressible?

Answer 23

co-repressor

Question 24

what does the co repressor do?

Answer 24

it binds to the repressor then binds to operator stopping transcription

Question 25

inducible ; normally structural genes are

Answer 25

not transcribed

Question 26

repressible; normally structural genes are

Answer 26

transcribed

Question 27

in positive inducible operons transcription is usually

Answer 27

off

Question 28

what does the substrate do in positive inducible?

Answer 28

makes the activator activate and transcription happen

Question 29

does the activator in positive inducible bind to the operator?

Answer 29

no

Question 30

in positive repressible product does what?

Answer 30

inactivates the regulatory protein and ends transcription

Question 31

product makes what?

Answer 31

the activator inactive

Question 32

what is the energy source of bacteria?

Answer 32

lactose

Question 33

lacI is what?

Answer 33

repressor with its own promoter

Question 34

lacO

Answer 34

operator where the repressor binds

Question 35

lacZ encodes what?

Answer 35

B-galactosidase

Question 36

b-galactosidase does what>

Answer 36

converts lactose to glucose and galactose. or lactose in allolactose.

Question 37

allolactose regulates what

Answer 37

lactose metabolism

Question 38

lac Y encodes what

Answer 38

permease

Question 39

lacA encodes what

Answer 39

transacetylase

Question 40

permease allows what

Answer 40

lactose to enter cell

Question 41

when lactose or allolactose are present what happens?

Answer 41

all genes are expressed to metabolize lactose. inducible

Question 42

lac operon is an example of what?

Answer 42

negative inducible

Question 43

what happens in the absense of lactose

Answer 43

repressor binds to operator and stops transcription

Question 44

in the absence of lactose, is the protein active or inactive?

Answer 44

active

Question 45

what happens to lac operon when high levels of glucose?

Answer 45

operon is off

Question 46

what controls the lac operon in the presence of glucose?

Answer 46

cap mechinism

Question 47

Cap binds to what to produce what?

Answer 47

camp forming the camp cap complex

Question 48

what does the camp cap complex do?

Answer 48

binds to promoter for DNA poly to bind for transcription

Question 49

when there are high levels of glucose, what is the level of camp cap

Answer 49

low levels.. no transcription

Question 50

when there are low levels of glucose, what is the level of camp cap?

Answer 50

high.. transcription takes place

Question 51

when glucose is low, what is produced?

Answer 51

glucose from lactose

Question 52

when glucose if high is anything produced?

Answer 52

no

Question 53

trp operon produces enzymes that what?

Answer 53

produce trytophan

Question 54

what type gene system is it?

Answer 54

negative repressible

Question 55

regulator protein is what?

Answer 55

repressor

Question 56

low levels of trytophan causes what

Answer 56

repressor cant bind, therefor transcription occurs and trytophan is produced

Question 57

trytophan is present

Answer 57

binds to repressor and which binds to operator and stops transctiption

Question 58

when talking about trytophan, when is the regulator active?

Answer 58

when trytophan is high