Ch7 Human transport

Question 1

Large organisms

Answer 1

1. lower SA:vol
2. more active
3. more specialised exchange surfaces
4. absorb gases, nutrients and remove excrement

Question 2

Tissue fluid

Answer 2

1. beginning of capillary bed
2. hydrostatic pressure of capillaries is greater than tissue fluid
3. fluid forced out of capillaries and into spaces around cells
4. hydrostatic pressure lower at venule end of capillary bed
5. wpt at venule end is lower than tissue fluid because high plasma proteins conc
6. water diffuses via osmosis back into capillaries

Question 3

Artery adaptation

Answer 3

1. thick and muscular
2. Elastic tissue for high pressure
3. no valves
4. smooth endothelium to reduce friction

Question 4

Arteriole adaptation

Answer 4

1. thicker muscle wall to restrict blood flow
2. thinner elastic layer for lower blood pressure

Question 5

Veins adaptation

Answer 5

1. thin muscle layer
2. thin elastic for lower blood pressure
3. wider lumen
4. valves to ensure no backwards flow

Question 6

Capillary adaptations

Answer 6

1. narrow lumen so red blood cells squeezed flat against side of capillary
2. numerous and highly branched large SA
3. single-celled wall for short diffusion pathway

Question 7

Ventricle adaptation

Answer 7

1. thicker and more muscular
2. contracts and pushes blood out

Question 8

Diastole

Answer 8

1. blood enters atria from pulmonary vein and vena cava
2. ventricles and atria relax
3. semi lunar valves close
4. increased pressure in atria(decreased volume)
5. atrioventricular valves open
6. blood flows passively into ventricles

Question 9

Atrial systole

Answer 9

1. atria contract
2. pushes blood into ventricles down pressure gradient
3. recoil of ventricle walls (slight increase in ventricalar pressure)

Question 10

Ventricular systole

Answer 10

1. atria relax
2. ventricles contract
3. decreased volume, increased pressure
4. atrioventricular valves shut (ventricles > atria pressure)
5. semi-lunar valves open
6. blood forced down pressure gradient into aorta and pulmonary artery

Question 11

Draw the cardiac cycle (pressure and volume)

Question 12

Cardiac output

Answer 12

heart rate x stroke volume

Question 13

Valves

Answer 13

1. pressure > convex side
2. open to let blood pass through
3. pressure > concave side
4. blood collects and don’t open
5. flow of blood in one direction

Question 14

Bicuspid valve

Answer 14

between left atrium and ventricle

Question 15

Tricuspid valve

Answer 15

between right atrium and ventricle

Question 16

Draw the heart

Question 17

Coronary arteries

Answer 17

1. branch off aorta
2. supply heart with oxygen

Question 18

Pulmonary vein

Answer 18

1. connected to left atrium
2. brings deoxygenated blood back from lungs

Question 19

Pulmonary artery

Answer 19

1. connected to right ventricle
2. carries deoxygenated blood from heart to lungs

Question 20

Vena cava

Answer 20

1. connected to right atrium
2. brings deoxygenated blood from tissues to the heart

Question 21

Aorta

Answer 21

1. connected to left ventricle
2. carries oxygenated blood from heart to tissue

Question 22

Elastic lining

Answer 22

1. Stretches under high pressure when ventricle
   contracts
2. Recoils under low pressure when ventricle relaxes
3. evens blood flow and pressure

Question 23

Muscle

Answer 23

1. contracts
2. reduces diameter of lumen
3. changes pressure and flow of blood