Which of the following statementscorrectly describes why a series of closely spa

ID: 3035 • Letter: W

Question

Which of the following statementscorrectly describes why a series of closely spaced actionpotentials causes a sustained contraction rather than a series ofclosely spaced twitches?

Ca2+ ions are released quickly fromtroponin, keeping the Ca2+ concentration in the cytosolhigh between closely spaced action potentials. Release of Ca2+ from thesarcoplasmic reticulum through channels is slow compared to theuptake of Ca2+ into the SR via ATP-dependent pumps,resulting in Ca2+ slowly trickling into the sarcomeresbetween closely spaced action potentials. When a series of action potentials is closelyspaced, there is not sufficient time for Ca2+ uptakeinto the sarcoplasmic reticulum between action potentials, andCa2+ remains bound to troponin throughout theseries. Fewer Ca2+ ions are released fromthe sarcoplasmic reticulum as a result of several closely spacedaction potentials than as a result of a single actionpotential. Which of the following statementscorrectly describes why a series of closely spaced actionpotentials causes a sustained contraction rather than a series ofclosely spaced twitches?

Ca2+ ions are released quickly fromtroponin, keeping the Ca2+ concentration in the cytosolhigh between closely spaced action potentials. Release of Ca2+ from thesarcoplasmic reticulum through channels is slow compared to theuptake of Ca2+ into the SR via ATP-dependent pumps,resulting in Ca2+ slowly trickling into the sarcomeresbetween closely spaced action potentials. When a series of action potentials is closelyspaced, there is not sufficient time for Ca2+ uptakeinto the sarcoplasmic reticulum between action potentials, andCa2+ remains bound to troponin throughout theseries. Fewer Ca2+ ions are released fromthe sarcoplasmic reticulum as a result of several closely spacedaction potentials than as a result of a single actionpotential.

Explanation / Answer

When a series of action potentials is closelyspaced, there is not sufficient time for Ca2+ uptakeinto the sarcoplasmic reticulum between action potentials, andCa2+ remains bound to troponin throughout theseries.

Navigate

Which of the following statementscorrectly describes why a series of closely spa

Which of the following statementsis CORRECT? a. Cost of preferred stock is the r

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.

Which of the following statementscorrectly describes why a series of closely spa

Question

Explanation / Answer

Related Questions

Navigate