the heart Flashcards
partial pressure of CO2 and O2
allows exchange
CHD risk factors
- risk factors: age, smoking, gender, stress, exercise, diet, genes
heart attack
blockage in a coronary artery > prevents flow of O2 > blood to that area > tissue dies, no O2 reaching it > heart cannot work effectively
what is the process of blood flowing through the heart?
- blood enters from left and right atrium
- atria contract and blood goes to ventricles
- ventricles contract and force blood out of the heart
where does the left pump blood?
what adaptation does it have for this?
around the entire body.
this is why it has thick muscular walls
where does the right pump blood?
to the lungs
adaptations of arteries (2)
- thick muscular walls
- elastic fibres stretch when blood surges through. they recoil between surges
what do arteries do?
carry very high pressure blood from the heart to the lungs
capillaries adaptations
very thin walls- short diffusion path.
what do capillaries do?
when blood flows through them, substances like glucose and oxygen diffuse into bodily cells. CO2 diffuses from the cells into the blood
what do veins do?
carry blood from the organs to the heart (at low pressure)
veins adaptations
- thin wall because of low blood pressure
- many contain valves that open and close to prevent the backflow/stopping of blood.
what are statins?
drugs which reduce the level of cholesterol in the blood
this slows down the rate of fatty materials building up in the arteries
pros of statins
proven to reduce the risk of CHD
cons of statins
cause liver problems
