cardio-respiratory and vasuclar systems: blood vessels

Question 1

decsribe arteries

Answer 1

• arteries carry blood away from the heart
• the biggest artery is the aorta, which carries blood from the left ventricle to the body
• blood is under high pressure
• they have muscular walls and a narrow diameter for blood. this allows the arteries to change diameter to vasoconstrict and vasodilate.

Question 2

describe veins

Answer 2

• beins carry blood back to the heart
• thinner walls than arteries
• blood under lower pressure
• larger internal diameter for blood flow

Question 3

describe capillaries

Answer 3

• capillaries are tiny, thin walled structures (1 cell thick)
• allows for diffusion of gas