Asked by Seher Veljee on May 25, 2024
Verified
After contraction has occurred, the Ca2+ are
A) destroyed by cholinesterase.
B) chemically bound to the cross bridges.
C) secreted by the Golgi apparatus to the outside of the cell.
D) released from troponin.
E) returned to the sarcolemma.
Cholinesterase
An enzyme that breaks down acetylcholine and other choline esters in the nervous system to terminate synaptic transmission.
Troponin
A protein complex involved in muscle contraction; often measured to diagnose heart attacks.
Sarcolemma
The thin, plasma membrane that surrounds the cytoplasm of muscle cells, critical in muscle contraction.
- Gain an understanding of how calcium contributes to muscle contraction.
Verified Answer
LG
Lexis GarciaMay 30, 2024
Final Answer :
D
Explanation :
The correct answer is that after contraction has occurred, the calcium ions (Ca2+) are released from troponin. This release allows the muscle to relax by enabling the tropomyosin to cover the binding sites on the actin filaments again, preventing further cross-bridge formation between actin and myosin, which is necessary for muscle contraction.
Learning Objectives
- Gain an understanding of how calcium contributes to muscle contraction.