Flashcards in B3 - Transporting Materials Deck (54)
What are the three parts of the blood circulation system?
-Blood vessels (pipes)
-The heart (pump)
What do each of the two circulations of blood do?
-Carry blood from the heart to the lungs and back.
-Carry blood around the rest of the body.
Why is a double circulation system efficient?
More areas of the blood can receive oxygenated blood quickly.
What carries blood away from the heart?
What returns blood to the heart?
What supplies the heart muscles with oxygen?
How many chambers does the heart have?
What are the two types of chamber in the heart?
Atria and ventricles
What is the vena cava?
The vein that brings deoxygenated blood to the heart.
What part of the heart does the vena cava link to?
What is the pulmonary vein?
The vein that brings oxygenated blood from the lungs.
How is blood moved from the atria to the ventricles?
The atria contract which forces blood down.
How is blood stopped from going back into the atria?
The atrioventricular valves close when the ventricles contract.
What are the two atrioventricular valves?
-Tricuspid on the right.
-Bicuspid on the left.
How is blood stopped from re-entering the ventricles?
Semi-lunar valves close.
What is the aorta?
An artery which takes blood around the body.
Why is the muscular heart wall thicker on the left?
So it can pump at a higher pressure allowing the blood to go around the body.
What are capillaries for?
They enable substances to diffuse easily into and out of cells.
Describe the structure of an artery.
-Thick layer of muscle and elastic fibres.
Describe the structure of a vein.
Describe the structure of a capillary.
-Walls a single cell thick.
What happens to the blood pressure as it flows through capillaries?
Why does the blood pressure change when passing through capillaries?
To allow for exchange of materials.
What happens to coronary arteries with age?
-They can become narrow.
-They get narrower as fatty deposits form.
What is a stent?
-A metal mesh which is placed in an artery.
How is a stent inserted?
-The stent and balloon are pushed up an artery.
-The balloon is inflated with the stent.
-The balloon is removed so the blood can flow freely.
What is bypass surgery?
Narrow or blocked arteries are replaced with bits of vein from other parts of the body.
Give two advantages of mechanical heart valves.
-They are long lasting.
-They are very effective.
Give a disadvantage of mechanical heart valves.
-The patient has to take anticoagulant drugs for the rest of their life.