March 29, 2022
Do you guys still remember how our bodies control out the internal environment in I/GCSE Biology?
When we exercise
- Heat production and body temperature increase when in a race compared to when resting
Why is our body kept at 37°C?
- Body = internal temperature of 37°C
- In I/GCSE Biology, temperature at which enzymes work best
- Enzymes = speed up chemical reactions in the body
- Slow chemical reactions if body under 37°C, even slower if above
- Enzymes change structure and stop working if temperature above 45°C
- Homeostasis = process of keeping things constant & balanced in body
- Salts (sodium chloride) needed to help body work properly
- Na and Cl levels in blood controlled by kidneys (lost when sweating)
- Need balance of ion and water levels (sports drinks help replace these)
- Glucose (supplied by blood) in sports drinks – helps top up blood sugar levels
Heat exhaustion and heatstroke
- Both heat related conditions
- Heat exhaustion – core temperature at 40°C (water and salt levels drop) symptoms = nausea, heavy sweat. When untreated = heatstroke
- Taken to cool place + drink lots of water
- In I/GCSE Biology, heatstroke – core temperature above 40°C. Cells break down & important parts of body stop working. Symptoms = confusion, unconsciousness. When untreated = multiple organ failure, brain damage, death
- Cool core temp – ice packs / cold shower
Balancing the water budget
- In I/GCSE Biology, loose water = urinate, pass faeces, sweat and air we breathe out (misty mirror when breathe on it)
- Kidneys control balance of water + ions in body.
- Do it by passing urine = contains excess salts + water + other waste materials (body doesn’t need these)
That's all~