Organisation PART 2

Question 1

Artery

Answer 1

Carries blood AWAY from the heart.

Thick muscular walls, small lumen, carry blood under high pressure carry oxygenated blood (except for the pulmonary artery).

Question 2

Vein

Answer 2

Carry blood to the heart.

Thin walls, large lumen, carry blood under low pressure, have valves to stop flow in the wrong direction. Carries deoxygenated blood (except for the pulmonary vein).

Question 3

Capillary

Answer 3

Connects arteries and veins.

One cell thick to allow diffusion, carry blood under very low pressure.

Question 4

Blood

Answer 4

Blood is a tissue consisting of plasma, in which blood cells, white blood cells and platelets are suspended.

Question 5

Plasma

Answer 5

55% of blood.
Pale yellow fluid.
Transports carbon dioxide, hormones and waste.

Question 6

Red blood cells

Answer 6

45% of blood.
Carries oxygen.
Large surface area, no nucleus, full of hemoglobin.

Question 7

Hemoglobin

Answer 7

A protein in the red blood cells that carries oxygen.

Question 8

White blood cells

Answer 8

<1% of blood.
Part of the immune system.
Some produce antibodies, others surround and engulf pathogens.

Question 9

Platelets

Answer 9

<1% of blood.
Fragments of cells.
Clump together to form blood clots.

Question 10

The heart

Answer 10

The heart is an organ that pumps blood around the body in a double circulatory system.
The heart pumps low oxygen/high carbon dioxide blood into the lungs for diffusion.

Question 11

Right ventricle

Answer 11

Pumps blood to the lungs where gas exchange takes place.

Question 12

Left ventricle

Answer 12

Pumps blood around the rest of the body.

Question 13

Pacemaker (in the right atrium)

Answer 13

Controls the natural resting heart rate. Artificial electrical pacemakers can be fitted to correct irregularities.

Question 14

Coronary arteries

Answer 14

Carry oxygenated blood to the cardiac muscle.

Question 15

Heart valves

Answer 15

Prevent blood in the heart from flowing in the wrong direction.

Question 16

Pulmonary artery (arteries but we don’t go into detail bout that)

Answer 16

Carries deoxygenated blood from right ventricle to the lungs.

Question 17

Pulmonary vein(s)

Answer 17

Carries oxygenated blood from your lungs to your heart’s left atrium.

Question 18

Aorta

Answer 18

Carries oxygenated blood from left ventricle to the rest of the body.

Question 19

Vena cava

Answer 19

Delivers deoxygenated blood from the rest of the body to the right atrium.

Question 20

Trachea

Answer 20

Carries air to/from the lungs.
Rings of cartilage to protect the airway.

Question 21

Bronchioles

Answer 21

Carries air to/from the air sacs (alveoli).
Splits into multiple pathways to reach all the air sacs.

Question 22

Alveoli

Answer 22

Site of gas exchange in the lungs.
Maximises surface area for efficient gas exchange.

Question 23

Capillaries (in gas exchange)

Answer 23

Wraps around alveoli.
Allows gas exchange between into/out of blood.
Oxygen diffuses into the blood and carbon dioxide diffuses out.