Questions and answers for exam Preparation

MCQs

Total Questions : 121 | Page 5 of 13 pages

Question 41. Which of the following is true about a hydrophilic signaling molecule?

Its receptor is located in the cytosol of the target cell
It might trigger a signal cascade that causes some effect in a cell
Since it can enter the cell, it directly affects some specific cell process
It is a steroid

Discuss Question

Answer: Option B. -> It might trigger a signal cascade that causes some effect in a cell
Answer: (b).It might trigger a signal cascade that causes some effect in a cell

Question 42. In terms of cell communication, what do bacterial pathogens such as cholera and anthrax have in common?

They destroy the receptors for key signaling molecules
They prevent the production of key signaling molecules
They alter the chemical structure of key signaling molecules
They block the normal functioning of signal transduction mechanisms

Discuss Question

Answer: Option D. -> They block the normal functioning of signal transduction mechanisms
Answer: (d).They block the normal functioning of signal transduction mechanisms

Question 43. CAMP and cGMP are derived from

ATP and GTP by the actions of adenylate cyclase and guanylate cyclase respectively
GTP and ATP by the actions of adenylate cyclase and guanylate cyclase respectively
ATP and GTP by the actions of guanylate cyclase and adenylate cyclase respectively
none of the above

Discuss Question

Answer: Option A. -> ATP and GTP by the actions of adenylate cyclase and guanylate cyclase respectively
Answer: (a).ATP and GTP by the actions of adenylate cyclase and guanylate cyclase respectively

Question 44. If a disease of the blood vessels caused the endothelial cells of the vessel to die, what effect would that have on the cellular activities associated with vasodilation?

Nitric oxide would no longer be produced
Smooth muscle cells could not be made to relax
It would be more difficult to increase blood flow and reduce blood pressure
All of the above

Discuss Question

Answer: Option D. -> All of the above
Answer: (d).All of the above

Question 45. Nitroglycerin has long been administered to human patients suffering from chronic chest pain (angina). This medication works because it

mimics the action of signal receptors
is broken down into hormones that affect the heart
interferes with chemical cascades that trigger contraction of heart muscle
breaks down into nitric oxide, which increases blood flow to the heart

Discuss Question

Answer: Option D. -> breaks down into nitric oxide, which increases blood flow to the heart
Answer: (d).breaks down into nitric oxide, which increases blood flow to the heart

Question 46. What is the name of the protein signaling molecule that alters glucose uptake, and where would its receptors be located?

Insulin; many different cell types that use glucose for fuel
Insulin; beta cells of the pancreas
PDGF; the blood
NGF; the nerves involved in simple reflexes

Discuss Question

Answer: Option A. -> Insulin; many different cell types that use glucose for fuel
Answer: (a).Insulin; many different cell types that use glucose for fuel

Question 47. Cell signaling can be classified into

three distinct types based on the distance over which the signaling molecules act
two distinct types based on the distance over which the signaling molecules act
three distinct types based on the signaling molecules
none of the above

Discuss Question

Answer: Option A. -> three distinct types based on the distance over which the signaling molecules act
Answer: (a).three distinct types based on the distance over which the signaling molecules act

Question 48. Which of the following statement is correct?

Cell communicate with one another in multicellular organisms using extracellular signaling molecules or hormones
Cell communicate with one another in unicellular organisms using extracellular signaling antigen and antibody
Cell communicate with one another in multicellular organisms using intracellular signaling molecules only
Cell communicate with one another in unicellular organisms using intracellular signaling antigen and antibody

Discuss Question

Answer: Option A. -> Cell communicate with one another in multicellular organisms using extracellular signaling molecules or hormones
Answer: (a).Cell communicate with one another in multicellular organisms using extracellular signaling molecules or hormones

Question 49. In the signal transduction mechanism known as protein phosphorylation