Question

Regulatory proteins in a myofibril are:

• A. Actin and myosin
• B. Troponin and actin
• C. Troponin and tropomyosin
• D. Actin and tropomyosin

Hint:

Troponin binds calcium, and tropomyosin shifts to expose myosin-binding sites on actin for muscle contraction.

Answer 1

The Correct Option is C

Step 1: Understanding Myofibril Regulation
- Troponin and tropomyosin regulate muscle contraction by controlling actin-myosin interaction.
- Actin and myosin are contractile proteins, not regulatory proteins.