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High yield Qs

11. In the lac operon the order of segments in the DNA is
A. operator, promoter, galactosidase, transferase, permease
B. operator, promoter, galactosidase, permease, transferase
C. promoter, operator, permease, transferase, galactosidase
D. promoter, operator, galactosidase, permease, transferase



12.In the lac operon, the role of the catabolite activator protein is to
A. insure the use of lactose before any other sugar
B. insure that lactose can enter the cell
C. insure that glucose is used before lactose
D. insure that glucose is stored for future use


13.A promoter that binds RNA polymerase strongly is said to be
A. enhanced
B. efficient
C. repressed
D. attenuated


14.The functioning of the catabolite activator protein requires the use of which intracellular messenger
A. nitric oxide
B. acetylcholine
C. GTP
D. cyclic AMP

11)D
12)C...but i'm not quite sure, everything else doesn't make much sense to me...
13)A
14)D

15.A zinc-finger protein controls the expression of genes by binding to
A. RNA
B. antigens
C. ribosomes
D. DNA

11..D
12.a
13.a
14.d
15.d

The correct answers are :

11.D
12.C
13.B
14.D
15.D

Thank you

Could u post the explanations plz!!!

Maryam, can u email me: Docmedra

some of this stuff isn't in kaplan, should we know it still?

@dane7

All Qs are basic and their explanations are included in each answer...most of them are also explained by the UW-Q bank /or Kaplan ln.

for example

11,12....the lac operon is the genetic sequence in the E.coli genome that codes for the metabolic of Lactose... In the lac operon the order of segments in the DNA is" promoter, operator, galactosidase, permease, transferase ....UW Qs ID...1478
.
13,14,15,refer to ."Regulation of gene expression......chapter 5"

Zinc finger....Kaplan pg72-73

hey maryam

c an u explain question 12 \

cuz i thought glucose dec cAMP which is needed for CAP which woud otherwise stimulate gene transcription

I mean CAP would stimulate lactose use???