the heart and blood vessels Flashcards
(17 cards)
right side of the heart pumps
deoxygenated blood
left side of the heart pumps
oxygenated blood
why is left ventricle thicker and muscular then right ventricle
left ventricle has to pump blood to all around the body so it need to contract powerfully, but the right ventricle has to carry the blood to the lungs.
why is ventricles thicker than atria
atria has to only push blood a small distance into the ventricles whereas the ventricles have to push the blood out of the lungs
av valves do
link to the ATRIA to the VENTRICLES.
prevents blood flowing back into the atria when the ventricles contact
sl valves do
links the AORTA to the PA
prevents blood flowing back into the heart after the ventricles contract
where do arteries carry the blood
from the heart to the rest of the body
where do veins carry the blood
take blood back into the heart
3 types of blood vessels
arteries
veins
cappilaries
why do arteries have thick wall, muscular, have elastic tissue and the endothelium folded
they have thick walls, muscular and have elatic tissues in the walls to cope with high pressure
The endothelium is folded which allows the artery to expand which also cope with high pressure
why is veins with very little elastic or muscle tissue
blood is under low pressure
where does metabolic exchange occur
Cappilaries
what to the network of capillaries (called capillary beds) do
increase the surface area for exchange
what is an advantage of capillaries being one cell thick
speeds us the diffusion of substance into and out of the cells
properties of arteries
they carry blood from the heart to the rest of the body.
Thick walled - cope high pressure
muscular - cope high pressure
elastic tissue - cope high pressure
inner lining (endothelium is folded) - allows artery to fold to help cope with high pressure
properties of veins
takes blood back to the heart
wider
very little elastic or muscle tissue - as they are under pressure
valves - prevent backflow
Blood flows through the veins by the help of contraction of the body muscles
properties of capillaries
smallest of the blood vessels
- where metabolic exchange occurs (movement of substances between blood in the capillaries and body cells) - It happens via diffusion, osmosis through the capillaries walls.
network of capillaries in tissue (called capillary bed) - increases the surface area for exchanges
One-cell thick walls → short diffusion distance in and out of the cells.
Narrow lumen → slows down blood flow → allows more time for exchange
