This member of the AKAP family, designated mAKAP, anchors both PDE and the regulatory subunit  of PKA to the nuclear membrane, maintaining them in a negative feedback loop that provides close local control of the ATP level and PKA activity.

B- The basal level of PDE activity in the presence of hormone (resting state) keeps cAMP levels below those necessary for PKA activation. 

C- Activation of β-adrenergic receptors causes an increase in cAMP to a level in excess of that which can be degraded by PDE. 

D- The resulting binding of cAMP to the R subunits of PKA releases the active catalytic (C) subunits into the cytosol. Some C subunits enter the nucleus, where they phosphorylate and thus activate certain transcription factors . Other C subunits phosphorylate PDE, stimulating its catalytic activity.

E-  Active PDE hydrolyzes cAMP, thereby driving cAMP levels back to basal levels and causing re-formation of the inactive PKA C-R complex. Subsequent de-phosphorylation of PDE returns the complex to the resting state.

TLS Online TPP Program

#Question id: 9273

#Unit 6. System Physiology – Plant

In the higher excited state, chlorophyll is extremely unstable; it rapidly gives up some of its energy to the surroundings as heat, and enters the lowest excited state, the excited chlorophyll has four alternative pathways for disposing of its available energy: fluorescence, Heat loss, energy transfer, photochemistry; all process takes place in which wavelength,

TLS Online TPP Program

#Question id: 9272

#Unit 6. System Physiology – Plant

The quantum yield of photosynthesis falls off drastically for far-red light of wavelengths greater than 680 nm, indicating that far-red light alone is inefficient in driving

photosynthesis, this effect is called

TLS Online TPP Program

#Question id: 9270

#Unit 6. System Physiology – Plant

In the lowest excited state, the excited chlorophyll has four alternative pathways for disposing of its available energy which of the statement of alternative pathway would be INCORRECT?

TLS Online TPP Program

#Question id: 9269

#Unit 6. System Physiology – Plant

The distribution of electrons in the excited molecule is somewhat different from the distribution in the groundstate molecule, Absorption of blue light excites the chlorophyll to a higher energy state than absorption of red light because

TLS Online TPP Program

#Question id: 11538

#Unit 7. System Physiology – Animal

Prostaglandins are local regulators whose chemical structure is derived from ________.

TLS Online TPP Program

#Question id: 11539

#Unit 7. System Physiology – Animal

Aspirin and ibuprofen both ________.