Cardiac Muscle Quiz

Cardiac Muscle

• Cardiac muscle, also known as myocardium, is responsible for the pumping action of the heart.

Cardiac vs Skeletal Muscle

• The main difference between cardiac muscle and skeletal muscle is that cardiac muscle is involuntary, meaning it contracts without conscious control, whereas skeletal muscle is voluntary, requiring conscious control to contract.

Length-Tension Relationship

• The length-tension relationship in cardiac muscle is physiologically relevant because it allows the heart to adjust its pumping force to adapt to changes in blood volume and pressure.
• This relationship describes how the tension generated by the cardiac muscle changes in response to alterations in the length of the muscle fibers.

Contractility

• The term for the ability of the heart to change its contractility is called intrinsic modulation.
• Intrinsic modulation enables the heart to adjust its pumping force to meet changing demands, such as increased blood pressure or increased oxygen demand.

Afterload and Stroke Volume

• Afterload, or the pressure against which the heart pumps, affects stroke volume by decreasing it when afterload is high.
• This occurs because high afterload increases the resistance to blood flow, making it more difficult for the heart to pump blood, resulting in a decreased stroke volume.