객관식
What is the part of a sarcomere that contains only thin filaments?
218
views
9. Muscle Tissue
Sliding Filament Theory and the Sarcomere
객관식
What causes the release of calcium ions into the sarcoplasm from the terminal cisterns during muscle contraction?
A
The depolarization of the T-tubules
B
The hydrolysis of ATP by myosin heads
C
The arrival of an action potential at the neuromuscular junction
D
The binding of acetylcholine to receptors on the sarcolemma
검증된 단계별 안내1
Understand the structure of a muscle fiber: Muscle fibers contain structures called sarcoplasmic reticulum (SR) and T-tubules. The SR stores calcium ions, and T-tubules are invaginations of the sarcolemma that help transmit electrical signals.
Recognize the role of calcium ions: Calcium ions are crucial for muscle contraction as they bind to troponin, causing a conformational change that allows myosin to bind to actin, initiating contraction.
Identify the process of muscle contraction initiation: An action potential travels along a motor neuron to the neuromuscular junction, where it triggers the release of the neurotransmitter acetylcholine.
Examine the role of acetylcholine: Acetylcholine binds to receptors on the sarcolemma, leading to depolarization and the generation of an action potential that travels along the sarcolemma and down the T-tubules.
Connect depolarization to calcium release: The depolarization of the T-tubules triggers the opening of calcium channels in the terminal cisterns of the sarcoplasmic reticulum, releasing calcium ions into the sarcoplasm and facilitating muscle contraction.
관련 영상
관련 실천
