Homeostasis key terms

Question 1

Homeostasis

Answer 1

the maintenance of a stable internal environment

Question 2

Negative feedback

Answer 2

the body’s mechanism for reversing change so it returns to normal

Question 3

Positive feedback

Answer 3

a deviation from optimum that causes further deviations away from the norm

Question 4

Glucagon

Answer 4

hormone that causes blood glucose concentration to rise

Question 5

Insulin

Answer 5

hormone that causes blood glucose concentration to lower

Question 6

Beta cells

Answer 6

secrete insulin

Question 7

Alpha cells

Answer 7

secrete glucagon

Question 8

Glycogenesis

Answer 8

enzymes in muscle + hepatocytes cells convert GLUCOSE INTO GLYCOGEN + fat
- cells can then store glycogen

Question 9

Glycogenolysis

Answer 9

breakdown of GLYCOGEN TO GLUCOSE
- liver converts the stored glycogen to release into blood

Question 10

Gluconeogensis

Answer 10

• production of GLUCOSE from OTHER SOURCES (amino acids + glycerol)

Question 11

Glucose transporters

Answer 11

channel proteins that allow glucose to be transported across a membrane

Question 12

adenylate cyclase

Answer 12

activated by adrenaline + glucagon

converts ATP into cyclic AMP

Question 13

cyclic AMP (cAMP)

Answer 13

Activates an enzyme - protein kinase A

Question 14

Protein kinase A

Answer 14

• activates cascade (chain of reactions ) that breaks glycogen into glucose

Question 15

Hyperglycaemia

Answer 15

HIGH blood glucose concentration
- lowers water potential leading to dehydration

Question 16

Hypoglycaemia

Answer 16

LOW blood glucose concentration
- cells become deprived of energy

Question 17

Nephron

Answer 17

functional unit of kindey

Question 18

Osmorecptors

Answer 18

detect changes to blood water potential
- in hypothalamus