The Cardiovascular System Overview
37 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What occurs during the depolarization phase of cardiac muscle action potentials?

  • Na+ channels open and Ca2+ channels close
  • K+ channels remain closed and Ca2+ channels close
  • Na+ channels close and K+ channels open
  • Na+ channels open and Ca2+ channels open (correct)

    • What is the role of the plateau phase in cardiac muscle action potentials?

  • It inhibits spontaneous action potentials
  • It allows for rapid repolarization
  • It prolongs the action potential duration (correct)
  • It triggers muscle contraction via Na+ influx

    • Which of the following is NOT part of the heart's conduction system?

  • Sinoatrial node
  • Purkinje fibers
  • Atrionodal junction (correct)
  • Atrioventricular node

    • During which phase do K+ channels open and Ca2+ channels close in cardiac muscle action potentials?

    <p>Repolarization phase</p> Signup and view all the answers

    How does the duration of cardiac muscle action potentials compare to that of skeletal muscle?

    <p>Cardiac action potentials are longer, taking 200-500 msec</p> Signup and view all the answers

    What is the primary function of the heart in the cardiovascular system?

    <p>To pump blood through the body</p> Signup and view all the answers

    How much blood does a healthy adult heart pump per minute at rest?

    <p>5 liters</p> Signup and view all the answers

    What are the two types of circulation associated with the heart?

    <p>Pulmonary and systemic circulation</p> Signup and view all the answers

    Which of the following is NOT a function of the heart?

    <p>Filters toxins from blood</p> Signup and view all the answers

    What characteristic compares the size of the heart to a common object?

    <p>Size of a fist</p> Signup and view all the answers

    What is the weight of the heart relative to common measurements?

    <p>Less than 1 pound</p> Signup and view all the answers

    What role does the right side of the heart play?

    <p>Pumps blood to the lungs for oxygenation</p> Signup and view all the answers

    For how long does a healthy heart typically pump at the same rate?

    <p>Around 75 years</p> Signup and view all the answers

    What occurs during atrial systole?

    <p>Contraction of the atria</p> Signup and view all the answers

    Which heart valves closure produces the first heart sound?

    <p>Atrioventricular valves</p> Signup and view all the answers

    What is the normal stroke volume in milliliters per heartbeat?

    <p>70 milliliters/beat</p> Signup and view all the answers

    What does cardiac output measure?

    <p>Volume of blood pumped by a ventricle in one minute</p> Signup and view all the answers

    What contributes to the production of the second heart sound?

    <p>Closure of the semilunar valves</p> Signup and view all the answers

    What is the average heart rate in beats per minute?

    <p>72 beats/min</p> Signup and view all the answers

    During ventricular diastole, what process takes place?

    <p>Relaxation of the ventricles</p> Signup and view all the answers

    What physiological event is directly associated with heart sounds?

    <p>Closure of heart valves</p> Signup and view all the answers

    What does cardiac output (CO) equal?

    <p>Stroke volume multiplied by heart rate</p> Signup and view all the answers

    Which term describes the amount of blood returning to the heart?

    <p>Venous return</p> Signup and view all the answers

    What effect does exercise have on venous return, preload, and stroke volume?

    <p>Increases all of them</p> Signup and view all the answers

    What is the concept of after load in the context of heart function?

    <p>The pressure against which ventricles must pump blood</p> Signup and view all the answers

    Which division of the autonomic nervous system is primarily responsible for the 'fight or flight' response affecting heart activity?

    <p>Sympathetic nervous system</p> Signup and view all the answers

    Which of the following best describes intrinsic regulation of the heart?

    <p>Mechanisms contained within the heart itself</p> Signup and view all the answers

    What is the role of baroreceptors in heart function?

    <p>To regulate heart function through blood pressure detection</p> Signup and view all the answers

    According to Starling’s Law of the Heart, what influences stroke volume?

    <p>Preload and after load relationship</p> Signup and view all the answers

    What role do baroreceptors play in the cardiovascular system?

    <p>They monitor blood pressure changes.</p> Signup and view all the answers

    How do changes in blood pressure affect baroreceptors?

    <p>They change the frequency of action potentials.</p> Signup and view all the answers

    Which chemicals can increase heart rate and stroke volume?

    <p>Epinephrine and norepinephrine</p> Signup and view all the answers

    What can decrease cardiac output?

    <p>Depression</p> Signup and view all the answers

    What condition is indicated by a lack of adequate blood supply to the cardiac muscle?

    <p>Coronary Artery Disease</p> Signup and view all the answers

    What is the main purpose of angioplasty?

    <p>To open blocked blood vessels</p> Signup and view all the answers

    What happens during a myocardial infarction?

    <p>Areas of cardiac muscle may die due to lack of blood supply.</p> Signup and view all the answers

    What is the function of a stent in cardiac procedures?

    <p>To keep blood vessels open.</p> Signup and view all the answers

    Study Notes

    The Cardiovascular System

    • The heart is a muscular organ that pumps blood through the body, it is part of the cardiovascular system.
    • Blood circulates through the body using two distinct systems: the pulmonary circulation and the systemic circulation.
    • The pulmonary circulation routes blood from the heart to the lungs to pick up oxygen and releases carbon dioxide.
    • The systemic circulation pumps oxygenated blood from the heart throughout the body and returns deoxygenated blood to the heart.

    Functions of the Heart

    • The heart generates blood pressure.
    • The heart routes blood through the body.
    • The heart ensures one-way flow of blood.
    • The heart regulates the supply of blood to tissues.

    Heart Characteristics

    • The heart is about the size of a fist and weighs less than a pound.
    • Cardiac muscle cells contract when stimulated by action potentials.
    • Action potentials of cardiac muscle cells are longer than action potentials of skeletal muscle cells.

    Conduction System of Heart

    • The conduction system of the heart is composed of specialized muscle cells that coordinate atrial and ventricular contractions.
    • Cells in the conduction system can produce spontaneous action potentials.
    • The conduction system includes: the sinoatrial node, atrioventricular node, atrioventricular bundle, right and left bundle branches, and Purkinje fibers.

    Cardiac Cycle

    • The cardiac cycle includes: atrial systole, ventricular systole, atrial diastole, and ventricular diastole.
    • Heart sounds are produced by the closing of heart valves.
    • The 'lubb' sound is caused by closure of the atrioventricular valves.
    • The 'dupp' sound is caused by closure of the semilunar valves.

    Regulation of Heart Function

    • Stroke volume is the volume of blood pumped per ventricle per contraction, roughly 70 milliliters per beat.
    • Heart rate is the number of heart beats per minute, approximately 72 beats per minute.
    • Cardiac output is the volume of blood pumped by a ventricle in 1 minute, roughly 5 liters/minute.
    • Cardiac output is calculated by multiplying stroke volume times heart rate.

    Intrinsic Regulation of the Heart

    • Intrinsic regulation refers to the heart's control of its own cardiac output.
    • Venous return is the amount of blood returning to the heart.
    • Preload is the degree of ventricular wall stretch at the end of diastole.
    • Preload, venous return, and stroke volume are linked.
    • Starling’s law of the heart explains the relationship between preload and stroke volume.
    • Afterload is the pressure against which ventricles must pump blood.

    Extrinsic Regulation of Heart

    • Extrinsic regulation uses external mechanisms, like the nervous and chemical systems, to control heart function.
    • The autonomic nervous system controls heart activity through the sympathetic and parasympathetic divisions.
    • The baroreceptor reflex regulates heart function by monitoring blood pressure.
    • The chemoreceptor reflex regulates heart function by sensing chemical changes in the blood.

    Heart Disease

    • Coronary artery disease occurs when blood supply to the heart muscle is decreased due to narrowed coronary arteries.
    • Myocardial infarction or heart attack occurs when one or more coronary arteries close, causing cardiac muscle lacking blood supply to die and scar.

    Heart Procedures

    • Angioplasty is a procedure used to open blocked blood vessels.
    • Stents are inserted to keep vessels open.
    • A bypass procedure reroutes blood away from blocked arteries.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Heart Lecture Outline PDF

    Description

    Explore the fundamentals of the cardiovascular system in this quiz, focusing on the heart's structure, functions, and circulation pathways. Understand how blood flows through the body and the important roles the heart plays in overall health.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser