Connections between thin filaments and thick filaments are known as: a. myofilaments b. Z lines...
Question:
Connections between thin filaments and thick filaments are known as:
a. myofilaments
b. Z lines
c. sarcomeres
d. cross-bridges
e. Y lines
The Sarcomere:
The sarcomere is the functional unit of muscle; it is the structure that shortens during muscle contraction. A sarcomere is comprised of overlapping myofilaments - thick filaments that are made of the protein myosin, and thin filaments made of the protein actin. The actin filaments partially overlap the myosin filaments on each side of the myosin filament, and the myosin filaments have "heads", or globular structures, on the end of the filament that stick out towards the actin filaments. There are binding sites for the myosin "heads" on the actin chains.
Answer and Explanation: 1
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View this answerWhen the muscle cell receives the signal to contract, the myosin heads reach up and bind to the sites on the actin filaments. These connections are...
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Cross-Bridge Cycle | Overview, Steps & Role of ATP
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Chapter 14 / Lesson 3
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Discover the cross-bridge cycle and its stages. Identify what a cross-bridge muscle contraction is and learn about the role of ATP in cross-bridge cycling.
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