Cell Surface Receptors: Types and Functions Practice Questions

Question 1

Which of the following is a metabotropic receptor?

Accepted Answer

Beta receptor for norepinephrine

Answer

GABA-A receptor

Answer

NMDA receptor

Answer

Nicotinic acetylcholine receptor

Question 2

If there is a Gs alpha subunit gain-of-function mutation, this results in

Accepted Answer

Increased cAMP

Answer

Decreased cAMP

Answer

Increased GTPase activity

Answer

Decreased IP₃

Question 3

Sequence the events in neuromuscular action potential conduction:
1. Sodium channels open in the end plate
2. Calcium enters at the nerve terminal
3. Release of acetylcholine

Accepted Answer

$2 \rightarrow 3 \rightarrow 1$

Answer

$1 \rightarrow 2 \rightarrow 3$

Answer

$1 \rightarrow 3 \rightarrow 2$

Answer

$3 \rightarrow 2 \rightarrow 1$

Question 4

Which of the following binds to intracellular receptors?

Accepted Answer

Estrogen

Answer

Growth hormone

Answer

Vitamin E

Answer

Insulin

Question 5

All the following  hormones have receptors on the plasma membrane of target tissues except:

Accepted Answer

Estradiol

Answer

Epinephrine

Answer

Glucagon

Answer

Thyrotropin

Question 6

One of the ways that cells communicate with each other is by secretion of various molecules. The secreted molecule is known as

Accepted Answer

A signaling molecule

Answer

A receptor molecule

Answer

An integrin

Answer

A spectrin tetramer

Question 7

Which of the following stimulate adenylate cyclase with G-protein coupled action ?

Accepted Answer

Cholera toxin

Answer

Shiga toxin

Answer

Diphtheria toxin

Answer

Pseudomonas toxin

Question 8

Which of the following statements about G protein-coupled receptors (GPCRs) is correct?

Accepted Answer

The alpha subunit of G proteins determines whether they are stimulatory or inhibitory.

Answer

G proteins bind hormones directly before transmitting signals to receptors.

Answer

G proteins are active when bound to GDP and inactive when bound to GTP.

Answer

G proteins require the beta and gamma subunits to remain bound to the alpha subunit to transmit signals.

Question 9

Which intervention is best in patients operated for bilateral acoustic neuroma for hearing rehabilitation?

Accepted Answer

Auditory brainstem implant (ABI)

Answer

Bilateral cochlear implant

Answer

Unilateral cochlear implant

Answer

High power hearing aid

Question 10

Which of the following statements best describes the mechanism of action of insulin on target cells?

Accepted Answer

Insulin binds to a transmembrane receptor on the outer surface of the plasma membrane, activating the tyrosine kinase in the cytosolic domain of the receptor.

Answer

Insulin binds to a receptor on the outer surface of the plasma membrane, activating adenylate cyclase through the Gs protein.

Answer

Insulin binds to a cytoplasmic receptor and is transferred as a hormone receptor complex to the nucleus to modulate gene expression.

Answer

Insulin enters the cell and causes the release of calcium ions from intracellular stores.

Cell Surface Receptors: Types and Functions — MCQs

Cell Surface Receptors: Types and Functions — MCQs

Want unlimited practice?