Temperature Control and Waste Removal
Ever wondered why you shiver when you're cold? Your body has an amazing control system that keeps your core body temperature at exactly 37°C, no matter what the weather's like outside.
The thermoregulatory centre in your brain's hypothalamus acts like a thermostat, constantly monitoring your blood temperature. When you're too cold, your muscles contract rapidly (shivering), which releases heat through respiration - a clever way your body warms itself up.
Your body also needs to get rid of toxic waste products through excretion. Carbon dioxide from respiration must be removed by your lungs because it makes your blood acidic and messes with enzyme function. Meanwhile, urea - a poisonous waste from breaking down proteins - gets filtered out by your kidneys.
Quick Fact: The liver converts highly toxic ammonia into less harmful urea through a process called deamination - basically removing the amino group from excess amino acids.
