Q NBME F1 S4

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Q NBME F1 S4

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8 Posts

usmleasr
Forum Guru

Topics: 105
Posts: 970

04/09/04 - 09:17 AM

The increase in the intracellular concentration of AMP in muscle after 15 minutes of strenuous exercise has which of the following effects?
A ) Increased activity of adenylyl cyclase
B ) Increased breakdown of glycogen
C ) Increased release of insulin
D ) Inhibition of phosphofructokinaseactivity
E ) Inhibition of pyruvate kinase activity

Malaysian
Forum Guru

Topics: 28
Posts: 778

04/09/04 - 09:35 AM

I think its E...inhibiting the Pyruvate Kinase causes formation of lactic acid.

Idiopathic
Forum Guru

Topics: 19
Posts: 641

04/09/04 - 10:01 AM

I really want to say B. No O2 to pull off the NADH causes the shunt to lactic acid, I dont think the increased AMP does that directly.

Malaysian
Forum Guru

Topics: 28
Posts: 778

04/09/04 - 10:29 AM

Yes you are right Idiopathic....i got my NADH and AMP confused.....increased AMP will lead to glycogenolysis

jalabert
Forum Newbie

Topics: 0
Posts: 30

04/09/04 - 11:11 AM

This question can be applied to any scenario which will induce a low energy state in the cell. Products of ATP degradation (e.g. ADP, AMP, Pi, IMP) all activate glycogenolysis, and glycolysis.

asmi
Forum Hero

Topics: 1043
Posts: 4,609

04/09/04 - 12:48 PM

good Q usmleasr smiling face

Thanks

laura81
Forum Elite

Topics: 32
Posts: 175

02/10/07 - 09:18 AM

what about A?

babydoc4usmle
Forum Guru
avatar

Topics: 18
Posts: 634

02/10/07 - 01:55 PM

not last 2 options
AMP catalases PFK-1, which produces product that stimulates PK (feed-forward) which is last substrate level phosphorylation
release of insulin in muscle cell??? something new for me
to get cAMP by A-cyclase we need ATP, not AMP
so we left with glycogenolysis as a source of energy
i stick with B

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