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receptor -
#1
mumbai

Of the following, which is unlikely to be associated with receptors bound to plasma membranes, their interaction with ligands, and the biologic response to this interaction?


Answer Choices : Correct answer : Your answer
A. Structurally, these receptors have hydrophobic amino acid domains, which are in contact with the membrane, and hydrophilic regions, which extend into the extracellular fluid and the cytoplasm
B. Chemical interactions of ligands with these receptors may involve the formation of many types of bonds, including ionic, hydrogen, van der Waals', and covalent
C. Ligand-receptor interactions are often stereospecific (i.e., one stereoisomer is usually more potent than the other)
D. In some cases, a ligand that acts as an agonist at membrane-bound receptors increases the activity of an intracellular second messenger
E. Activation of membrane-bound receptors and subsequent intracellular events elicit a biologic response through the transcription of DNA

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#2
vdew

D???
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#3
mumbai

is ir 1more mistake usmleasy ,they have given ans E
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#4
DI

no the answer is E because response through the transcription of DNA is for nuclear receptors
eg steroid hormones

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#5
img

D is right cos ligand receptor act as agonist inc the response by 2nd messenger,for e.f glucagon binding with alpha recptor will inc the response by cAMP
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#6
mash

E
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#7
amruta

the answer is E
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#8
mumbai

di and amruta
if u guys r thinking about steroid and giving ans as D then pls make a note that they dont have receptor on plasma membrane ,being lipid soluble they can easily go through membrane and bind to there receptor in plasma or at nucleus.
off course glucagon does stimulate DNA trancription ,but that also it does via intracellular second messenger system only
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#9
mumbai

soo whats the conclusion guys
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