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+--- Thread: Molecular biology....11,12,13,14,15 - maryam2009 (/showthread.php?tid=643106)
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Molecular biology....11,12,13,14,15 - maryam2009 - ArchivalUser - 12-27-2011
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
0 - ArchivalUser - 12-27-2011
11)D
12)C...but i'm not quite sure, everything else doesn't make much sense to me...
13)A
14)D
0 - ArchivalUser - 12-27-2011
15.A zinc-finger protein controls the expression of genes by binding to
A. RNA
B. antigens
C. ribosomes
D. DNA
0 - ArchivalUser - 12-27-2011
11..D
12.a
13.a
14.d
15.d
0 - ArchivalUser - 12-27-2011
The correct answers are :
11.D
12.C
13.B
14.D
15.D
Thank you
0 - ArchivalUser - 12-27-2011
Could u post the explanations plz!!!
0 - ArchivalUser - 12-27-2011
Maryam, can u email me: Docmedra
0 - ArchivalUser - 12-27-2011
some of this stuff isn't in kaplan, should we know it still?
0 - ArchivalUser - 12-27-2011
@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
0 - ArchivalUser - 04-07-2012
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???