Smooth Muscle MCQ Quiz | Nerve-Muscle

Welcome to the Smooth Muscle MCQ Quiz, specifically designed for MBBS students studying the Nerve-Muscle block. This quiz will test your understanding of the histology, physiology, and pharmacology of smooth muscle. Topics covered include contractile mechanisms involving calcium-calmodulin, the roles of MLCK and MLCP, differences between unitary and multi-unit smooth muscle, autonomic innervation, and the unique properties like the latch-bridge mechanism and stress-relaxation. This assessment contains 25 multiple-choice questions to help you consolidate your knowledge and prepare for your examinations. After submitting your answers, you will see your score and a detailed review of each question. You can also download all the questions with their correct answers in a PDF format for future revision. Good luck!

1. In smooth muscle, calcium initiates contraction by binding to which of the following proteins?

2. Which of the following structures in smooth muscle is functionally analogous to the Z-discs of skeletal muscle?

3. The “latch-bridge” mechanism in smooth muscle is responsible for:

4. Multi-unit smooth muscle is characteristically found in the:

5. The upstroke of the action potential in visceral smooth muscle is primarily caused by the influx of:

6. Which enzyme is directly responsible for the phosphorylation of myosin light chains in smooth muscle?

7. Nitric oxide (NO) induces smooth muscle relaxation by activating guanylate cyclase, leading to an increase in:

8. The slow waves in gastrointestinal smooth muscle are generated by:

9. A key difference between unitary and multi-unit smooth muscle is the presence of numerous ________ in unitary smooth muscle.

10. The phenomenon where a stretched smooth muscle slowly relaxes over time, allowing an organ like the bladder to accommodate more volume, is called:

11. Which protein is conspicuously absent in the contractile apparatus of smooth muscle compared to skeletal muscle?

12. Calcium for smooth muscle contraction is sourced from:

13. Dephosphorylation of myosin light chains by Myosin Light Chain Phosphatase (MLCP) leads to:

14. Which statement about smooth muscle contraction is TRUE compared to skeletal muscle?

15. Stimulation of Alpha-1 adrenergic receptors on vascular smooth muscle by norepinephrine leads to:

16. The rudimentary invaginations of the cell membrane in smooth muscle cells, which are analogous to T-tubules, are called:

17. Which of the following is an example of unitary (visceral) smooth muscle?

18. In pharmacomechanical coupling, smooth muscle contraction occurs without a significant change in:

19. The ratio of actin to myosin filaments in smooth muscle is approximately:

20. Calcium channel blockers like Nifedipine cause smooth muscle relaxation primarily by:

21. Which hormone is a potent stimulator of uterine smooth muscle contraction?

22. Unlike skeletal muscle, smooth muscle cells lack:

23. Caldesmon and calponin are regulatory proteins in smooth muscle that are thought to:

24. The resting membrane potential of a typical smooth muscle cell is:

25. Smooth muscle is primarily innervated by the: