Regulating Stroke Volume, Skeletal Muscle Pump and Frank-Starling Mechanism

What is the difference between end diastolic volume (EDV) and end systolic volume (ESV)?

• EDV is the volume of blood in the ventricle after contraction, ESV is before contraction.

• EDV is the volume of blood in the ventricle before contraction, ESV is after contraction.

• EDV is the volume of blood in the atria, ESV is in the ventricle.

• EDV and ESV are the same.

How can the stroke volume be increased?

• By increasing the end diastolic volume.

• By increasing the end systolic volume.

• By decreasing the end diastolic volume.

• By decreasing both EDV and ESV.

What effect does increasing the time before ventricular contraction have on stroke volume?

• It only affects heart rate.

• It has no effect on stroke volume.

• It increases the stroke volume.

• It decreases the stroke volume.

What is the primary function of the skeletal muscle pump?

• To regulate blood pressure.

• To pump blood out of the heart.

• To increase venous return to the heart.

• To decrease heart rate.

How do veins ensure one-way blood flow?

• Through muscle contractions.

• By being closer to the heart.

• By using valves that prevent backflow.

• By having thicker walls than arteries.

What is the role of sarcomeres in muscle contraction?

• They are the functional units of contraction.

• They regulate heart rate.

• They store calcium ions.

• They transport oxygen in the blood.

What happens when the heart muscle stretches due to increased blood volume?

• The contraction strength decreases.

• The heart rate decreases.

• The heart stops contracting.

• The contraction strength increases.

What is the Frank-Starling mechanism?

• A way to increase end systolic volume.

• A method to reduce blood pressure.

• A mechanism that increases stroke volume with more blood in the heart.

• A process that decreases heart rate.

How does calcium affect muscle contraction in the heart?

• It only affects skeletal muscles.

• It increases the affinity of troponin for calcium ions.

• It decreases the affinity of troponin for myosin.

• It has no effect on muscle contraction.

What is the result of increased affinity of troponin for calcium ions?

• Stronger muscle contractions.

• Weaker muscle contractions.

• No change in muscle contractions.

• Decreased stroke volume.