B12 - Homeostasis in Action

Question 1

name:

3 methods of cooling down

homeostasis

Answer 1

• vascodialation
• sweat
• hairs lie flat

Question 2

name:

the part of the hypothalumus that controls temperature

Answer 2

thermoregulatory centre

Question 3

name:

4 methods of keeping warm

homeostasis

Answer 3

• vasoconstriction
• less sweat
• hairs erect
• shivering

Question 4

explain:

vascodialation

Answer 4

1. capillaries near the surface of skin dialate
2. so, more radiation of energy

Question 5

explain:

sweating

Answer 5

1. water evapourates from the skin
2. energy transferrred to surroundings

Question 6

explain:

shivering

Answer 6

1. rapid muscle contractions
2. respiration occurs which is exothermic

Question 7

How is carbon dioxide removed from the body?

Answer 7

blood transports to the lungs which is then exhaled

Question 8

How is urea removed from the body?

Answer 8

filtered by the kidneys and passed out in urine, also in sweat

Question 9

How are water and mineral ions removed from the body?

Answer 9

through urine and sweat

Question 10

name:

the 3 stages of the kidney

Answer 10

1. filtration
2. selective reabsorbsion
3. urine production

Question 11

purpose of nephrons

Answer 11

microscopic filtering units that remove:
- urea
- excess water
- mineral ions

Question 12

describe:

filtration

in the kidneys

Answer 12

1. blood passes capillaries under high pressure
2. small molecules like urea, water, mineral ions pass into the nephrons

Question 13

purpose of ADH

Answer 13

a hormone which regulates how much water is reabsorbed by the kidneys

Question 14

what stimuli triggers ADH secretion

Answer 14

water concentration in blood in a negative feedback loop

Question 15

define:

dialisis

Answer 15

funciton of the kidney is carried out artificially

Question 16

explain:

purpose of dialisis fluid

Answer 16

using concentration gradients to filter out substances from the blood

Question 17

list:

substances inside dialisis fluid

Answer 17

dialysis fluid has the same concentration of glucose and mineral ions as the blood of a person without kidney disease

Question 18

name:

the main problem with kidney transplants

Answer 18

doner kidney is rejected by the recipient’s body

Question 19

explain:

Why are doner kidneys sometimes rejected?

Answer 19

antigens of the kidney are deteced by the immune system as foreign

Question 20

list 2:

methods of reducing kidney rejection

Answer 20

• close match of antigens
• drugs supressing immune system (immunosuppressant)