Podcast
Questions and Answers
Which chamber of the heart contains deoxygenated blood?
Which chamber of the heart contains deoxygenated blood?
The heart is located in the abdominal cavity.
The heart is located in the abdominal cavity.
False
What is the primary function of the heart?
What is the primary function of the heart?
To pump blood into the blood vessels.
The _____ is a large artery that carries oxygenated blood away from the heart.
The _____ is a large artery that carries oxygenated blood away from the heart.
Signup and view all the answers
Match the parts of the heart with their descriptions:
Match the parts of the heart with their descriptions:
Signup and view all the answers
What forms the apex of the heart?
What forms the apex of the heart?
Signup and view all the answers
The apex of the heart is located at the left 5th intercostal space, 9 cm from the middle line.
The apex of the heart is located at the left 5th intercostal space, 9 cm from the middle line.
Signup and view all the answers
What is the primary function of the left ventricle?
What is the primary function of the left ventricle?
Signup and view all the answers
The right atrium collects ______ blood from the body.
The right atrium collects ______ blood from the body.
Signup and view all the answers
Match the following heart chambers with their functions:
Match the following heart chambers with their functions:
Signup and view all the answers
Study Notes
Cardiovascular System (CVS)
- The CVS is formed by the heart and blood vessels (arteries and veins) and circulating blood.
Learning Objectives
- Describe the structures that create the cardiovascular system
- List the heart chambers
- Differentiate between pulmonary, systemic and portal circulations
- List and differentiate types of blood vessels
- Describe the connections between arteries and veins
The Heart
- Definition: A pump that propels blood into blood vessels.
- Location: Within the thoracic cavity, behind the sternum and costal cartilages (ribs 2-6), between the lungs.
- Structure: Composed of four chambers: two atria and two ventricles.
External Features of the Heart
- Atria (two):
- Right atrium
- Left atrium
- Ventricles (two):
- Right ventricle
- Left ventricle
Heart, Anterior View
- The heart is divided into two halves by a septum.
- The right side receives deoxygenated blood.
- The left side receives oxygenated blood.
The Heart (cont.)
- The right and left sides of the heart are completely separated by septa (interatrial and interventricular) preventing mixing of oxygenated and deoxygenated blood. The right side contains impure (deoxygenated) blood, and the left side contains pure (oxygenated) blood.
The Heart (cont.)
- Major blood vessels connected to the heart:
- Veins:
- Superior vena cava
- Inferior vena cava
- Four pulmonary veins
- Arteries:
- Aorta
- Pulmonary artery
- Veins:
The Heart (cont.)
- Apex:
- Cone-shaped structure.
- Points downwards, forwards, and to the left.
- Formed only by the left ventricle.
- Location of the Apex:
- Located at the left 5th intercostal space, 9 cm from the middle line, just below the left nipple.
The Heart (cont.)
- Borders:
- Upper border: Primarily formed by the two atria (mostly the left).
- Lower border: Formed by the right ventricle and the apical part of the left ventricle.
- Right border: Formed by the right atrium.
- Left border: Formed by the left ventricle.
The Heart (cont.) — Surfaces
- Sternocostal surface: Made up of atrial and ventricular parts.
- Atrial part: Primarily formed by the right atrium..
- Ventricular part: Formed by the right ventricle (right ½) and the left ventricle (left ½).
- Diaphragmatic surface: Rests on the diaphragm. Formed by the right ventricle (right ½) and left ventricle (left ½).
Functions of the Four Chambers
- Atria:
- Right atrium collects venous blood from the body
- Left atrium receives oxygenated blood from the lungs
- Ventricles:
- Right ventricle pumps blood to the lungs
- Left ventricle pumps blood to the entire body
Difference in Thickness of Ventricular Wall
- Left ventricle has a much thicker wall than the right ventricle due to the greater force needed to pump blood throughout the body.
Heart Valves
- Permit blood flow in only one direction.
- Prevent backflow (regurgitation).
- Valves between the atria and ventricles:
- Mitral valve (between left atrium & left ventricle)
- Tricuspid valve (between right atrium & right ventricle)
- Valves guarding the aorta and pulmonary trunk:
- Aortic valve
- Pulmonary valve
Direction of Blood Inside the Heart
- Blood flows through the heart in a specific pathway ensuring adequate oxygenation.
- Deoxygenated blood enters the right atrium from superior and inferior vena cava
- Flows through the tricuspid valve to right ventricle
- Contraction forces pulmonary valve open, blood flows to the pulmonary artery
- Blood flows to the lungs, where it releases CO2 and absorbs O2
- Oxygenated blood returns through pulmonary veins to the left atrium
- Flows through bicuspid valve to left ventricle
- Contraction forces aortic valve open, blood flows to the aorta
- Blood is distributed to the body, where it releases O2 and absorbs CO2
Circulation of Blood
- Two types of circulation: pulmonary and systemic.
- Pulmonary circuit:
- Carries deoxygenated blood from the heart to the lungs and back to the heart as oxygenated blood.
- Systemic circuit:
- Carries oxygenated blood from the heart to the body and back to the heart as deoxygenated blood.
Types of Circulation
- Systemic circulation:
- Oxygenated blood is pumped from the left ventricle through the aorta to the rest of the body
- Cells release oxygen and absorb CO2 in the body tissues.
- Deoxygenated blood returns to the right atrium through the superior and inferior vena cava.
- Pulmonary circulation:
- Deoxygenated blood is pumped from the right ventricle into the pulmonary artery.
- Blood is oxygenated in the lungs and returns to the left atrium via the pulmonary vein.
- Portal Circulation:
- Venous blood collects from the digestive tract and flows into the portal vein.
- Blood enters the liver where nutrients are absorbed, processed and metabolized.
The Blood Vessels
- Arteries:
- Carry oxygenated blood away from the heart (except pulmonary arteries).
- Thick-walled, narrow lumen.
- Branch into arterioles.
- Veins:
- Carry deoxygenated blood towards the heart (except pulmonary veins).
- Thin-walled, wide lumen.
- Collect from tributaries (venules).
Capillaries
- Minute vessels with thin walls and regular diameter
- Present in all parts of the body
- Site of exchange between blood and tissues
Arteriovenous Shunts
- Direct connections between small arterioles and venules
- Present in lips and nose
- Surrounded by sphincters to control blood flow and body temperature.
Sinusoids
- Irregular, wide thin-walled spaces
- Present in liver and spleen.
Wavy Arteries
- Supply movable organs (facial artery, splenic artery)
- Or expansile organs (uterine artery, lingual artery)
Arterial Anastomosis
- Multiple branches joining two arteries.
- Allows collateral circulation if one artery is blocked.
- Primarily found around joints.
End Arteries
- Arteries without anastomoses.
- If the end artery is obstructed, the tissues supplied by it suffer infarction.
- Examples include central retinal artery, coronary arteries.
Connections Between Arteries and Veins
- Capillaries form a network connecting arterioles to venules.
- Blood flows from arteries into capillaries, and from capillaries into veins.
Varicose Veins
- Backflow of blood into superficial veins
- Causes veins to become dilated and tortuous.
- Increased intra-luminal pressure (pressure within the vein).
Venipuncture
- Practice of obtaining intravenous access.
- Used to provide fluids, medications and obtain blood samples.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge about the human heart with this quiz! Covering its anatomy, functions, and the chambers that hold deoxygenated or oxygenated blood, this quiz is designed to evaluate your understanding of cardiovascular structure. Get ready to match parts of the heart with their descriptions and discover key functions!
