homeostasis Flashcards
1
Q
why is it important to maitain a constant body temp
A
- preventing damage to p.l membranes
- prevent enzymes denaturing
- ensure there is sufficient kinetic energy + therefore high ror
2
Q
what happens @ low blood glucose
A
- glucagon released
- activates enzymes that:
- glycogen converted to glucose (glycogenolysis)
- amino acids converted to glucose (gluconeogenesis)
- by liverrr
3
Q
what happens @ hi blood glucose
A
- insulin secreted by pancreas
- increases permeability of cells to glucose
- increases number of glucose carrier proteins
- increases f.diffusion into liver cell
- activate enzymes for glycogenesis (gluc –> glyc)
- stimulate fat synthesis in adipose tissue
4
Q
islet of langerhans (a + b)
A
Alpha cell - detects decrease in blood gluc conc (GLUCAGON)
Beta cell - detects increase in blood gluc conc (INSULIN)
5
Q
second messenger model
A
- (adrenaline + glucagon) 1st messengers
- when they bind they activate adenylate cyclate
- converts atp to camp (2m)
- camp binds to + activates protein kinase
6
Q
why does diabetes = more urine
A
- high conc of glucosse in glomerular filtrate
- glucose carrier proteins r all saturated
- hi glucose in filtrate lowers water potential
- (less steep conc grad) so less glucose reabsorbed into blood via osmosis
7
Q
gh
A
