Podcast
Questions and Answers
Which type of muscle is responsible for the pumping action of the heart?
Which type of muscle is responsible for the pumping action of the heart?
- Cardiac muscle (correct)
- Smooth muscle
- Muscle fibers
- Skeletal muscle
What is the main difference between cardiac muscle and skeletal muscle?
What is the main difference between cardiac muscle and skeletal muscle?
- Cardiac muscle is found in the heart while skeletal muscle is found throughout the body
- Cardiac muscle is multinucleated while skeletal muscle is uninucleated
- Cardiac muscle has striations while skeletal muscle does not
- Cardiac muscle is involuntary while skeletal muscle is voluntary (correct)
What is the physiologic relevance of the length-tension relationship in cardiac muscle?
What is the physiologic relevance of the length-tension relationship in cardiac muscle?
- It regulates the heart rate
- It determines the strength of the heart's contraction (correct)
- It affects the electrical conduction in the heart
- It controls the relaxation of the heart
What is the term for the ability of the heart to change its contractility?
What is the term for the ability of the heart to change its contractility?
How does afterload affect stroke volume?
How does afterload affect stroke volume?
Flashcards
Cardiac Muscle
Cardiac Muscle
A specialized type of muscle found only in the heart, responsible for its rhythmic contractions.
Involuntary vs. Voluntary
Involuntary vs. Voluntary
Cardiac muscle contracts involuntarily, meaning it's not consciously controlled, while skeletal muscle contracts voluntarily.
Length-Tension Relationship in Cardiac Muscle
Length-Tension Relationship in Cardiac Muscle
The relationship between the length of cardiac muscle fibers and the strength of their contraction.
Inotropism
Inotropism
Signup and view all the flashcards
Afterload
Afterload
Signup and view all the flashcards
Study Notes
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.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on cardiac muscle with this quiz. Explore the physiology and pathophysiology of the heart while reviewing key concepts from Costanzo Physiology and BRS Physiology. Be prepared for Medical Physiology I Lecture #26 on 9/18/2023 at 10am.
