MCQ on Signal Transduction with Answers: 

1. The information which is represented by a signal is detected by specific receptors and converted to a cellular response; this conversion is called _____________

A. Signal amplification

B. Signal transversion

C. Signal transduction

D. Signal integration

Answer: C

2. Regarding signal transduction, which of the following statements is true

A. Only excitable cells can transmit signals

B. Information encoded by action potentials is conducted across synapses

C. External stimuli are conducted on any receptor cell

D. Information enters the cell and causes a cellular response.

Answer: D

3. Which of the following is not an essential characteristic of receptors_______

A. Specificity 

B. Affinity 

C. Saturation 

D. Fidelity 

Answer: D

4. Signal transduction steps between cells, the links involving signal molecules are not included

A. is specifically recognized by receptors

B. from extracellular to intracellular

C. Act on second messengers to directly initiate cellular responses

D. Act on intracellular signal transduction molecules to initiate cellular responses

Answer: C

5. Acetylcholine receptor ion channel is an example of_____________

A. Gated ion channel

B. Receptor enzymes

C. Membrane protein

D. Nuclear protein

Answer: A

6. Extracellular signaling molecules (ligands) do not include

A. Hormones 

B. Cyclins 

C. Neurotransmitters 

D. Cell adhesion molecules

Answer: B

7. Features of signal transduction generally do not include_____

A. Transient and memory 

B. Temporary and reversible

C. Coherence of transduction pathways 

D. Specificity and heritability

Answer: D

8. In signal transduction, two types of enzymes that can cause protein conformational changes are______

A. Protein Kinases and Phosphatases 

B. Tyrosine Protein Kinases and Tyrosinase

C. Protein Kinase A and Protein Kinase C 

D. MAPK and MAPKK

Answer: A

9. Insulin receptor is an example of_____________

A. Steroid receptors

B. Serpentine receptors

C. Adhesion receptors

D. Receptor enzymes

Answer: D

10. The receptor that directly performs the catalytic function of the enzyme after binding to the ligand is________

A. Growth factor receptors 

B. Ion channel receptors 

C. G protein coupled receptors

D. Nuclear receptors

Answer: A

11. The protein with GTPase activity is______

A. G protein coupled receptor 

B. G protein 

C. Guanylate cyclase

D. Protein Kinase A 

Answer: B

12. PKA, PKC, PKG, CaMK, MAPK catalyze which of the following phosphorylation

A. Tyr residues 

B. Protein kinase  

C. Protein kinase A

D. Ser/Thr residues

Answer: D

13. Cell surface molecules involved in communication do not include

A. Ion channel 

B. IP 3 

C. Glycoprotein 

D. Phosphatidylserine

Answer: B

14. Which of the following molecules is not a G protein______

A. GTP-binding protein 

B. Guanylate-binding protein 

C. Ras

D. G-actin

Answer: D

15. Which of the following statements is true about the cAMP signaling pathway________

A. Discovered when insulin is first administered

B. G proteins, subunits bind to adenylate cyclase

C. Phosphodiesterase inhibitors promote cAMP degradation

D. G proteins are divided into inhibitory and excitatory types

Answer: D

16. Interferon receptors belong to______

A. Cytokine receptors 

B. Tyrosine protein kinase receptors 

C. Ion channel-coupled receptors

D. Nuclear receptors 

Answer: A

17. Which of the following are cell membrane receptors_______

A. Growth factor receptors 

B. Neurotransmitter receptors 

C. G protein-coupled receptors 

D. All of these 

Answer: D