Circulatory System: Blood Vessels Flashcards
Our blood makes it’s why around our body via blood vessels, name the three different types
– arteries
– capillaries
– veins
Which way do arteries carry blood? (hint: from where to where)
Arteries carry blood from the heart to the body/cells/organs
List the three adaptions arteries have to cope with the higher blood pressure from the heart, and explain them
– fibrous walls to keep arteries open/keep them from bursting
– elastic helps artery stretch under pressure and they’ll expand + contract as the heart pumps
– smooth muscle to aid smoother blood flow and to speed up the blood flow
True or false: artery walls are thicker then the size of their lumen. Explain.
Arteries have small lumens as they’re narrow on the inside (because of thick walls, muscle etc..) so this is true
Explain how the hardening of arteries can lead to heart attacks and heart failure (6-7)
– hardening of arteries mean loss of elasticity
– loss of elasticity means that there will be higher blood pressure
– this means that heart has to work harder to pump the blood and force it through the arteries and to the organs/body
– this means that the left ventricle will have to harden which makes it thicken and enlarge
– when it thickens and enlarges it’ll become stiff and weak
– stiff and weak ventricles can’t hold enough blood or as much as it used to
– this leads to heart failure and heart attack
What will arteries eventually branch into?
Capillaries
What are capillaries involved in? (hint: their job)
They’re involved with exchange of materials at the tissue
Why are capillaries responsible for exchange?
They carry the blood close enough to all the body cells so it can exchange with them
What do the capillaries exchange with the body cells?
Food and oxygen from the blood to the cells and CO2 and possibly urea from the cells to the blood
List three adaptions the capillaries have to aid exchange/diffusion
– they have permeable walls so substances that are being exchanged can diffuse through the walls
– their walls are one cell thick which lessens distance the substances need to diffuse across, increasing rate of diffusion
– they’re also narrow, which give them a large SA compared to their volume which’ll increase rate of diffusion
List one disadvantage of capillaries having a small lumen
– because the capillaries have a small lumen, it often forces the red blood cells to bend to fit through
– forcing blood through small spaces causes friction, which will cause a drop in blood pressure
What will capillaries eventually join up to form?
Veins
Where do the veins take the blood? (hint: from where to where)
The veins take blood from the the body/organs/cells back to the heart
True or False: veins carry low pressure blood
True
Why don’t veins need to have a thick wall like the arteries?
Veins carry lower pressured blood so their walls don’t need to be as thick or as strong
