The blood system Flashcards
What is the role of the circulatory system?
Transporting substances around the body.
What is the heart?
An organ that pumps blood around the body.
What is the wall of the heart made of?
Muscle tissues.
What are the two seperate circulation systems for?
Lungs and all other organs of the body.
Why is the muscular heart wall thicker on the left?
It has to pump blood all around the body.
Characteristic of arteries
Have thick walls containg muscle and elastic fibres.
Small lumen
Away from the heart
Blood high pressure
Vein
Thin walls.
Valves to prevent back-flow of blood
Blood low pressure
Capillaries
Narrow, thin-walled vessels.
When are stents needed?
Arteries begin to narrow and restrict blood flow due to fatty deposits.
How does blood flow around the heart?
Vena cava - DEOXYGENATED BLOOD into heart
Right atrium - contracts + force blood into right ventricle
Right ventricle - contracts + force blood out of heart to lungs
Pulmonary artery - DEOXYGENTAED BLOOD to lungs
Pulmonary vein - OXYGENATED BLOOD from lungs
Left atrium
Left ventricle
Aorta - OXYGENATED BLOOD around body
What is the role of valve?
Ensuring that blood flows in the correct direction
What carry blood from heart to organs?
Arteries
What carry blood from organs from heart?
Veins
What happens in capillaries?
Blood flows through capillaries in organs
Substances needed by cells in body tissues pass out of blood
Substances produced by cells pass into blood
Through walls of capillaries
What is the role of coronary arteries?
Supplying the heart muscle with oxygenated blood.
