What is the role of Ca2+ in muscle contraction?
Ca2+ ions play an important role in muscle contraction by creating interactions between the proteins, myosin and actin. The Ca2+ ions bind to the C component of the actin filament, which exposes the binding site for the myosin head to bind to in order to stimulate a muscle contraction.
What is the role of Ca2+ ions in muscle contraction quizlet?
What is the role of calcium ions in the contraction of skeletal muscle? The release of calcium ions triggers the immediate regeneration of creatine phosphate to power the contraction. Calcium ions bind to the troponin-tropomyosin complex and remove their inhibitory action on actin/myosin interaction.
Why is calcium important for muscle contraction quizlet?
Why is calcium necessary for muscle contraction? Calcium is needed to activate troponin so that tropomyosin can be moved to expose the myosin-binding sites on the actin filament. Calcium is needed to allow the muscle fiber to become depolarized.
Which of the following correctly describes the role of Ca2+ in the sarcomere?
Which of the following statements correctly describe(s) the relationship between Ca2+ concentration in the cytosol and the response in the sarcomere? –Increasing Ca2+ concentration causes movement of tropomyosin, exposing myosin-binding sites on actin.
What does calcium help the muscle contract quizlet?
Why is calcium necessary for muscle contraction? Calcium is needed to detach the myosin from the actin. Calcium is needed to allow the muscle fiber to become depolarized. Calcium is needed to activate troponin so that tropomyosin can be moved to expose the myosin-binding sites on the actin filament.
Which statement correctly describes the role of calcium Ca2 +) ions in the contractility of muscle cells myocytes in the heart?
Which of the following best describes the role of calcium (Ca2+) in the excitation-contraction coupling reaction? Ca2+ will bind to troponin, which leads to a conformational shift in tropomyosin, allowing for actin and myosin to attach.
Which statement best describes the importance of calcium in skeletal muscle contraction?
Which statement best describes the importance of calcium in skeletal muscle contraction? Calcium released from the sarcoplasmic reticulum binds to troponin to initiate muscle contraction.
Which of the following best describes the role of calcium Ca2+ in the excitation contraction coupling reaction?
Which of the following best describes the role of calcium (Ca2+) in the excitation-contraction coupling reaction? Ca2+ will bind to troponin, which leads to a conformational shift in tropomyosin, allowing for actin and myosin to attach.
How do acetylcholinesterase and Ca2+ pumps function in the relaxation of a muscle?
How do acetylcholinesterase and Ca2+ pumps function in the relaxation of a muscle? Acetylcholinesterase degrades acetylcholine in the synaptic cleft, decreasing its effect, and consequently the excitation of the muscle fiber. Without further stimulation, calcium channels within the sarcoplasmic reticulum close.
Where do calcium ions bind during a muscle contraction?
If present, calcium ions bind to troponin, causing conformational changes in troponin that allow tropomyosin to move away from the myosin binding sites on actin. Once the tropomyosin is removed, a cross-bridge can form between actin and myosin, triggering contraction.
Where do calcium ions bind during a muscle contraction quizlet?
What structures do the calcium ions bind to when muscle contraction is initiated? the actin filaments and the myosin heads. In response to an action potential entering the neuron, calcium ions diffuse from the sarcolemma into the sarcoplasm.
How do calcium ions initiate contraction in skeletal muscle fibers quizlet?
How do calcium ions initiate contraction in skeletal muscle fibers? Calcium ions bind to troponin, changing troponin's shape. Calcium ions provide the energy necessary for the myosin head power stroke.
How do calcium ions initiate contraction in skeletal muscle fibers?
(1) Calcium binds to troponin C, causing the conformational shift in tropomyosin that reveals myosin-binding sites on actin. (2) ATP then binds to myosin. (3) ATP is then hydrolyzed. (4) A cross-bridge forms and myosin binds to a new position on actin.