structures and functions

Question 1

relate the structure of arteries to their function

Answer 1

• thick, muscular walls to handle high pressure without tearing
• elastic tissue allows recoil to prevent pressure surges
• narrow lumen to maintain pressure

Question 2

relate the structure of veins to their function

Answer 2

• thin walls due to lower pressure
• require valves to ensure blood doesn’t flow backwards
• have less muscular and elastic tissue as they don’t have to control blood flow

Question 3

relate the structure of capillaries to their function

Answer 3

• walls only one cell thick: short diffusion pathway
• very narrow, so can permeate tissues and red blood cells can lie flat against the wall, effectively delivering oxygen to tissues
• numerous and highly branched, providing a large surface area

Question 4

relate the structure of arterioles and venules to their function

Answer 4

• branch off arteries and veins in order to feed blood into capillaries
• smaller than arteries and veins so that the change in pressure is more gradual as blood passes through increasingly small vessels