Transport in Humans

Question 1

What are the parts of the heart?

Answer 1

aorta
pulmonary vein
left atrium
AV valve
left ventricle
semi-lunar valve
right ventricle
AV valve
right atrium
vena cava
pulmonary artery

Question 2

Which side of the heart has thicker walls?

Answer 2

side with the left atrium & ventricle
- to generate pressure

Question 3

How does vaccination work?

Answer 3

involves injecting person with dead/weakened form of pathogen so person generates more memory cells
- white blood cells produce antibodies quickly if reinfection occurs

Question 4

What do arteries do?

Answer 4

carry blood away from heart, pump blood under high pressure so have thick muscular walls to withstand without damage

Question 5

What features do arteries have?

Answer 5

small lumen
thick, muscular layer with elastic fibres

Question 6

What do veins do?

Answer 6

carry blood towards heart, slower at lower pressure, so have thinner walls & large lumen with valves to prevent back-flow of blood

Question 7

What features do veins have?

Answer 7

large lumen
thin layer of muscle & elastic fibre
valves

Question 8

What do capillaries do?

Answer 8

tiny blood vessels, connect veins & arteries, extremely small (1 cell thick) & contain small holes (pores), to allows substances to pass through easily

Question 9

What features do capillaries have?

Answer 9

very small lumen
wall 1 cell thick

Question 10

What is the blood made up of?

Answer 10

• platelets - form blood clots at wounds to prevent blood loss & entry of pathogens
• white blood cells - detect pathogens & initiate immune response
• plasma - liquid containing CO2, digested food molecules, urea, hormones & heat energy
• red blood cells - carries oxygen to body tissue

Question 11

What 2 processes do white blood cells do?

Answer 11

• phagocytosis - white blood cell engulfs & digest pathogen
• antibody production - white blood cells release antibodies, with a complementary shape to pathogen, antibody bids to pathogen & makes it harmless

Question 12

How are red blood cells adapted for transporting oxygen?

Answer 12

• biconcave disc shape - maximum surface area for diffusion of oxygen
• small & flexible - squeeze through small capillaries
• contain haemoglobin - bind with oxygen
• no nucleus - can pack more oxygen into cells

Question 13

What is coronary heart disease caused by?

Answer 13

blockage in a coronary artery
blood is’t supplied to heart so doesn’t receive oxygen for aerobic respiration, preventing muscle contraction

Question 14

What factors increase the risk of coronary heart disease?

Answer 14

smoking
high saturated fat & salt diet
high blood pressure