Cardiovascular System Flashcards
Uses of the cardiovascular system
To transport nutrients, gases and waste products around the body
To protect the body from infection and blood loss
To help maintain a constant body temprature
To help maintain fluid balance in the body
Components of the cardiovascular system
Heart
Blood Vessels
Blood
Superior and Inferior Vena Cava
The two major veins carrying deoxygenated blood into the heart.
Superior carries blood from the superior (higher) part of the body
Inferior carries blood from the inferior (lower) part of the body
Right Atrium
The first chamber of the heart
Tricuspid Valve
Allows the deoxygenated blood to move from the Right atrium to the right ventricle.
Pulmonary Valve
Allows the deoxygenated blood to move from right ventricle into the pulmonary artery.
Pulmonary Artery
Transports the deoxygenated blood to the lungs to complete gas exchange
Pulmonary Vein
Transports oxygenated blood to the Left atrium.
Left atrium
The third chamber of the heart.
Mitral Valve
Transports oxygenated blood from the left atrium to the left ventricle
Left Ventricle
Fourth chamber of the heart, very large muscle wall
Aortic valve
Allows oxygenated blood to leave the left ventricle and go up the aorta to supply blood to the rest of the body.
Valves
Prevent the back flow of blood and makes it a one way system
Pericardium
The outside layer of the heart wall, made of epithileal and connective tissue
The pericardium has a pericardial cavity which allows the heart to expand and contract
Endocardium
The inside layer of the heart wall, made up of epithelial and connective tissue
Myocardium
The middle layer of the heart wall, made of cardiac muscle
Cardiac muscle
A tissue made up of cardiac myocytes.
Made up of striated (striped), branched and unnucleated fibres
Fibres joined by intercelated disks that conduct electrical impulses from one cell to another
ATP
Adenosine tri-phosphate is the energy currency of the body. Produced by the mitochondria and allows cardiac muscles to contract.
Name the types of blood vessels
Veins, arteries, venules, arterioles and capillaries
Capillaries
The type of blood vessels where gas exchange occurs again. It happens next to tissues. Wall is made of a single layer of cells.
Veins
Thin layer of muscle and elastic fibre, large lumen and thin outer wall.
Have valves which prevent back flow
Takes blood back to the heart
Artery
Thick outer wall, thick layer of muscle and elastic fibres, small lumen
Pushes blood away from the heart
Factors in pulse
Rhythm, strength, lying or standing, anxiety levels
Measured in bpm
Blood
Liquid that carries oxygen, nutrients and waste products around the body.
Made up of erthyrocytes, leukocytes, plasma and platelets in different concentrations
Sinoatrial Node
Nervous Tissue
Natural pacemaker of the heart, causes all heart beats and determines the heart rate.
Stimulates both left and right atria and causes them to contract, to allow the last 30% of deoxygenated blood to flow into the ventricles.
Atrioventricular Node
Nervous Tissue
Delays the passage of electrical impulses to the ventricles. This is to make sure the atria have ejected all the blood into the ventricles before the ventricles contract.
Bundle of HIS
Nervous Tissue
Also known as the AV bundle.
Takes the signal from the AV node and divides them into left and right bundles
Left and Right bundle branch
Nervous Tissue
Conducts the electrical signals to the apex (tip) of the heart. Which then spreads to purkinje fibres.
Purkinje Fibres
Nervous Tissue
Turns upwards and spreads electricle signals through the whole ventricular myocardium.
Depolarisation
Depolarisation through cardiomyocytes will cause the cardiac muscle to contract.
P Wave
When atria are full of blood the SA node fires, cause the mocardial cells in the atriums to depolarise and contract, this forms a P wave on the ECG reading.
P-Q Signal
The time taken for the electrical signal to travel from the SA node to the AV node.
QRS Complex
Represents the firing of the AV node and the depolarisation of the ventricles, whaich causes them to contract
S-T Signal
Plateau in the hearts action potential, this is when the ventricles contract and pump blood.
T wave
Shows ventricular repolarization directly before ventricular relaxation.
Systole
When atria or ventricles are contracting
Atrial systole 0.1 seconds
Ventricle systole 0.3 seconds
Diastole
When the atria or the ventricles are relaxed.
Complete diastole 0.4 seconds
