Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction.
- Calcium
- Magnesium
- Sodium
- Potassium
Answer
(1) Calcium
Solution
As per NCERT, the neural signal releases Ca2+ ions into the sarcoplasm.
⇒ Ca2+ binds with a subunit of troponin on actin filaments, removing the masking of active sites for myosin.
∴ Myosin heads bind to the exposed active sites on actin to form cross bridges.
Answer: (1)