blood vessels and cardiac cycle

Question 1

adaptations and features of arteries?

Answer 1

thick muscular walls to cope with high blood pressure in order to get more blood round the body quicker containing more oxygen
carries blood away from the heart
small lumen to allow for vasodilation, vasoconstriction

Question 2

what is vasodilation

Answer 2

vasodilation is when the lumen expands to allow more blood flow
e.g. to the working muscles during exercise

Question 3

what is vasoconstriction

Answer 3

vasoconstriction is when the lumen constricts to reduce blood flow
e.g. to organs during exercise

Question 4

adaptations and features of a vein

Answer 4

carry blood towards the heart
thin walls to cope with the low blood pressure
large lumen
have valves to prevent back flow
gets co2 to lungs quicker so we can diffuse & breathe it out

Question 5

adaptations and features of the capillaries

Answer 5

diffuses oxygen with alveoli
one cell thick
semi - permeable membrane
large surface area in body
join arteries and veins