11.1 What is Homeostasis?

  • Definition: The regulation of internal conditions to maintain a stable environment.
  • Importance: Ensures optimal conditions for enzyme activity and cell function.

11.2 Regulation of Blood Glucose

  • Insulin: Lowers blood glucose by facilitating glucose uptake.
  • Glucagon: Raises blood glucose by stimulating glycogen breakdown.

11.3 Regulation of Body Temperature

  • Thermoregulation: Maintaining body temperature around 37°C.
  • Mechanisms:
    • Vasodilation: Blood vessels widen to release heat.
    • Vasoconstriction: Blood vessels narrow to retain heat.
    • Sweating: Evaporation of sweat cools the body.
    • Shivering: Muscle contractions generate heat.

11.4 Excretion of Urea

  • Urea is a waste product of protein metabolism, excreted by the kidneys.