Question

Q1. Which of the following is a characteristic of a smooth muscle cell?

Select one:

a. It has T tubules to bring action potentials into the cell

b. It can be stimulated by hormones

c. It is under the control of the somatic nervous system

d. It relies on calcium which comes exclusively from the sarcoplasmic reticulum

Q2. Which of the following tissues does NOT have nicotinic receptors?

Select one:

a. motor end plate in the neuromuscular junction

b. adrenal medulla

c. cell bodies in a terminal ganglion

d. smooth muscle

e. more than one of the above does not have nicotinic receptors

Q3. Which of the following does NOT contain smooth muscle?

Select one:

a. blood vessel

b. digestive tract

c. heart

d. bronchioles

e. eyes

f. more than one of the above is correct

Answer 1

1.b)It can be stimulated by hormones

Acetylcholine has direct effect on contraction,and in blood vessels it acts indirectly through secondary agent and cause relaxation.It is under the control of autonomic nervous system,the calicum needed comes from outside the cell which induces sarcoplasmic reticulum to release calcium.

2.d)smooth muscle

Nicotinic receptors are present in neuromuscular junction ,cell bodies of terminal ganglion and adrenal medulla.

3.c) Heart

Smooth muscles are present in blood vessel ,digestive tract,respiratory bronchiolesand eyes,it is an involuntary muscle,non striated ,single nucleus and not branched.

Heart is made up of cardiac muscle,it is involuntary,striated,single nucleus and branched.