Asked by Breanna Andrade on Jul 14, 2024
Verified
In smooth muscle, cross-bridging occurs due to
A) Ca2+ binding to troponin.
B) Ca2+ binding to calmodulin.
C) myosin kinase adding a phosphate to myosin heads.
D) both Ca2+ binding to troponin and calmodulin.
E) both Ca2+ binding to calmodulin and myosin kinase adding a phosphate to myosin heads.
Ca2+ Binding
The process by which calcium ions (Ca2+) bind to specific molecules or cellular components, playing crucial roles in various biological processes including muscle contraction and neurotransmitter release.
Cross-bridging
refers to the interaction between actin and myosin filaments in muscle fibers during contraction, allowing for force generation.
Myosin Kinase
An enzyme that phosphorylates myosin light chains, which is crucial in the contraction of muscle cells.
- Comprehend the mechanisms of muscle contraction at the molecular level, including the role of calcium and specific enzymes.
Verified Answer
KW
Kamaya WrightJul 21, 2024
Final Answer :
E
Explanation :
In smooth muscle, cross-bridging is facilitated by calcium ions binding to calmodulin, which then activates myosin kinase. Myosin kinase phosphorylates myosin heads, enabling them to bind to actin.
Learning Objectives
- Comprehend the mechanisms of muscle contraction at the molecular level, including the role of calcium and specific enzymes.