Biochemistry Questions and Answers – Receptor Enzymes

This set of Biochemistry Multiple Choice Questions & Answers (MCQs) focuses on “Receptor Enzymes”.

1. SH2 domain specifically binds to _____________
a) GDP
b) Ca+2
c) Phosphorylated tyrosine residues
d) Phosphorylated serine residues
View Answer

Answer: c
Explanation: Phosphorylated tyrosine residues specifically binds SH2 domain during signal transduction.

2. cAMP and cGMP are derived from ____________
a) ATP and GTP by the actions of guanylate cyclase and adenylate cyclase respectively
b) ATP and GTP by the actions of adenylate cyclase and gualnlate cyclase respectively
c) GTP and ATP by the actions of adenylate cyclase and guanylate cyclase respectively
d) None of the mentioned
View Answer

Answer: b
Explanation: cGMP is derived from GTP by the actions of guanylate cyclase and
cAMP is derived from ATP by the actions of adenylate cyclase respectively.

3. Which of the following is false about phosphorylation by IRS on serine residue?
a) It is an inhibitory phosphorylation
b) It is molecular mechanism for insulin resistance
c) It increases insulin levels
d) Target tissues fail to respond to circulating insulin
View Answer

Answer: c
Explanation: Inhibitory serine phosphorylation is a molecular mechanism for insulin resistance which is a condition where target tissues fail to respond to circulating insulin.
advertisement
advertisement

4. The enzyme activated by cyclic AMP, passing on the hormonal signal is ____________
a) Protein kinase B
b) Protein kinase A
c) Protein kinase C
d) G protein receptor kinase
View Answer

Answer: b
Explanation: Protein kinase A is activated by cyclic AMP, passing on the hormonal signal.

5. Protein kinase ERK is activated by phosphorylation of ____________
a) Only Thr
b) Only Tyr
c) Both Thr and Tyr
d) Only Ser
View Answer

Answer: c
Explanation: Both Thr and Tyr are phosphorylated to activate the protein kinase ERK.
Sanfoundry Certification Contest of the Month is Live. 100+ Subjects. Participate Now!

6. Activation of guanylyl cyclase produces ____________
a) Guanosine 3’, 5’-cyclic monophosphate
b) Guanosine 2’, 5’-cyclic monophosphate
c) Guanosine 4’, 5’-cyclic monophosphate
d) Guanosine 1’, 5’-cyclic monophosphate
View Answer

Answer: a
Explanation: Guanosine 3’, 5’-cyclic monophosphate is produced by the activation of guanylyl cyclase.

7. cGMP-dependent protein kinase is also called ____________
a) Protein kinase B
b) Protein kinase A
c) Protein kinase G
d) Protein kinase C
View Answer

Answer: c
Explanation: cGMP-dependent protein kinase is also called protein kinase G.
advertisement

8. Which of the following is not responsible of producing diarrhea?
a) Elevation in [cGMP]
b) Increase in Cl secretion
c) Decrease in reabsorption of water by the intestinal epithelium
d) Decrease in Cl secretion
View Answer

Answer: d
Explanation: Elevation in [cGMP] leads to increase in Cl secretion and decrease in reabsorption of water by the intestinal epithelium.

9. Which of the following is a short-lived messenger that acts by stimulating a soluble guanylyl cyclase, raising [cGMP] and stimulating PKG?
a) NO
b) NO2
c) NO3
d) N2O
View Answer

Answer: a
Explanation: NO is a short-lived messenger that acts by stimulating a soluble guanylyl cyclase, raising [cGMP] and stimulating PKG.
advertisement

10. Ras protein is a ____________
a) G-protein switch
b) Small monomeric GTPase switch protein
c) Serine-threonine kinase
d) Tyrosine kinase
View Answer

Answer: b
Explanation: Ras protein is a small monomeric GTPase switch protein, involved in transmitting signals within cells.

Sanfoundry Global Education & Learning Series – Biochemistry.

To practice all areas of Biochemistry, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & discussions at Telegram SanfoundryClasses.