Homeostasis, Nutrition, Digestion Flashcards
What happens 1st when you stop eating?
- Breakdown glycogen
- about 6 hours after feeding – after turn to fatty acids
Phase 2 after not eating
- Ketosis, fat-burning
- Ketone bodies replace energy fuel
- Athletes may be in it more often
- Brain cannot directly use these, too thick to fit through the BBB
- Brain drains last of glucose
- Recalibrates requirement starts eating ketone bodies
Phase 3 - not eating
Protein burning, rapid muscle depletion
- The body starts eating itself – catabolises
- Mostly, cardiac arrest kills you – tissue degradation
A loss of more than ____% of water can be deadly
12%
How is the shape of enzymes determined?
Hydrogen bonding
Role of Kidneys
Filter blood
remove waste and excess solutes
Urea
Byproduct of protein metabolism
Ammonia
Toxic
How do kidneys work?
- Enter through renal artery
- Branch to specialized capillaries (glomerulus)
- Arterial pressure forces water/solutes out of capillaries
- Into tubule/collecting duct
Nutrients processed by kidney
Glucose, sodium, chloride
Wastes process by kidneys
Urea, creatinine
How do we regulate heat?
a) Conduction
b) Radiation
c) Evaporation
Example: Conduction
Lizard pressed against warm rock
Example: Radiation
Light coloured butterfly gains less heat then dark one
Example: Evaporation
sweating, panting
Endotherms
Maintain a high body temp in cold environments
Ectotherms
depend on environmental heat to maintain their body temperature