Engineering Questions with Answers - Multiple Choice Questions
MCQs on Cell Signaling and Signal Transduction – Crosstalk among Pathways
Which of the following does not converge to activate the same signaling pathway?
a) G-protein coupled receptor
b) Receptor tyrosine kinase
Explanation: The three types of cell surface receptors – G-protein coupled receptors, receptor tyrosine kinases and integrins, all can converge to lead to the formation of phosphotyrosine docking sites for the SH2 domain of the adaptor protein Grb2 in close proximity to the plasma membrane.
Cyclic AMP can inhibit the growth of cells.
Explanation: Cyclic AMP acts as an initiator of cascade that leads to mobilization of glucose. However it can also act to inhibit a variety of cells by blocking signals transmitted through MAP kinase cascade.
. Activation of P13K in adherent epithelial cell promotes ___________________
a) glucose translocation
b) cell survival
c) cell transformation
d) signal transduction
Explanation: P13K is an enzyme that gets activated by a wide range of stimuli. In adherent epithelial cells P13K promotes cell survival, while in an insulin-stimulated liver cell it promotes GLUT4 translocation and protein synthesis.
CREB is a _____________________
a) transcription factor
b) primary messenger
c) secondary messenger
d) surface receptor
Explanation: CREB is a transcription factor that also acts as an important signaling effector. It is a substrate for a wide range of kinases including cyclic AMP-dependent kinase, protein kinase A.