Unit 5 biology notes
Table of Contents
Organs and systems..................................................................1
The cardiovascular system...............................................................2
Structure and function of the heart............................................................................2
Calculation of Cardiac Output.....................................................................................4
Characteristic features of blood vessels and pressure changes..................................4
Blood transfusion and the ABO-Rhesus System..........................................................5
Cardiac Cycle.............................................................................................................. 9
Role of major blood vessels........................................................................................9
Opening and closing of heart valves.........................................................................10
ECGs (Electrocardiograms).......................................................................................10
Arrhythmia................................................................................................................ 10
Cardiovascular Disease (CVD)..................................................................................12
Organs and systems
, The cardiovascular system
Structure and function of the heart
Atria: The heart has two atria (right and left), which are the upper
chambers. Their role is to receive blood returning to the heart, the
right atrium receives deoxygenated blood from the body via the
vena cava, and the left atrium receives oxygenated blood from
the lungs via the pulmonary veins.
Ventricles: The heart also has two ventricles (right and left), which
are the lower chambers. Their role is to pump blood out of the heat.
The right ventricle pumps deoxygenated blood to the lungs via
the pulmonary artery and the left ventricle pumps oxygenated
blood to the body via the aorta.
Septum: The septum is the muscular wall that separates the left
and right sides of the heart. The function of the septum is to
prevent the mixing of deoxygenated blood between the left
and right sides of the heart.
Valves: The role of valves is to ensure that blood flows in one
direction through the heart preventing backflow.
Types of valves: Tricuspid valve, bicuspid valve (mitral valve), semi-
lunar valves. Tricuspid valve is located between the right and
left ventricle. The bicuspid valve (mitral valve) is located
between the left atrium and the left ventricle. Semi-lunar
valves are found at the entrances to the pulmonary artery and
aorta, preventing backflow into the ventricles.
Vena cava: The vena cava is the largest vein in the body with two
parts: the superior vena cava (drains blood from the upper
body) and the inferior vena cava (drains blood from the lower
body). The function of the vena cava is it carries deoxygenated
blood from the body to the atrium.
Pulmonary vein: The function of the pulmonary vein is it carries
oxygenated blood from the lungs to the left atrium.
Pulmonary artery: The role of the pulmonary artery is it carries
deoxygenated blood from the right ventricle to the lungs.
Table of Contents
Organs and systems..................................................................1
The cardiovascular system...............................................................2
Structure and function of the heart............................................................................2
Calculation of Cardiac Output.....................................................................................4
Characteristic features of blood vessels and pressure changes..................................4
Blood transfusion and the ABO-Rhesus System..........................................................5
Cardiac Cycle.............................................................................................................. 9
Role of major blood vessels........................................................................................9
Opening and closing of heart valves.........................................................................10
ECGs (Electrocardiograms).......................................................................................10
Arrhythmia................................................................................................................ 10
Cardiovascular Disease (CVD)..................................................................................12
Organs and systems
, The cardiovascular system
Structure and function of the heart
Atria: The heart has two atria (right and left), which are the upper
chambers. Their role is to receive blood returning to the heart, the
right atrium receives deoxygenated blood from the body via the
vena cava, and the left atrium receives oxygenated blood from
the lungs via the pulmonary veins.
Ventricles: The heart also has two ventricles (right and left), which
are the lower chambers. Their role is to pump blood out of the heat.
The right ventricle pumps deoxygenated blood to the lungs via
the pulmonary artery and the left ventricle pumps oxygenated
blood to the body via the aorta.
Septum: The septum is the muscular wall that separates the left
and right sides of the heart. The function of the septum is to
prevent the mixing of deoxygenated blood between the left
and right sides of the heart.
Valves: The role of valves is to ensure that blood flows in one
direction through the heart preventing backflow.
Types of valves: Tricuspid valve, bicuspid valve (mitral valve), semi-
lunar valves. Tricuspid valve is located between the right and
left ventricle. The bicuspid valve (mitral valve) is located
between the left atrium and the left ventricle. Semi-lunar
valves are found at the entrances to the pulmonary artery and
aorta, preventing backflow into the ventricles.
Vena cava: The vena cava is the largest vein in the body with two
parts: the superior vena cava (drains blood from the upper
body) and the inferior vena cava (drains blood from the lower
body). The function of the vena cava is it carries deoxygenated
blood from the body to the atrium.
Pulmonary vein: The function of the pulmonary vein is it carries
oxygenated blood from the lungs to the left atrium.
Pulmonary artery: The role of the pulmonary artery is it carries
deoxygenated blood from the right ventricle to the lungs.
