Summary
Homeostasis in mammals involves maintaining stable internal conditions essential for optimal cell function and enzyme activity. It includes processes like osmoregulation, blood glucose regulation, and excretion.
- Homeostasis — the process of keeping a body's internal circumstances constant.
Example: Maintaining core body temperature. - Negative Feedback — a mechanism that reverses a change to keep a physiological factor within a normal range.
Example: Regulation of blood glucose levels. - Osmoregulation — the control of water potential in body fluids.
Example: ADH regulating water reabsorption in kidneys. - Deamination — the removal of an amino group from an amino acid.
Example: Conversion of excess amino acids into urea in the liver. - Nephron — the functional unit of the kidney responsible for urine production.
Example: Filtration and reabsorption processes in the nephron. - Glucagon — a hormone that raises blood glucose levels.
Example: Secreted by α cells in the pancreas. - Insulin — a hormone that lowers blood glucose levels.
Example: Secreted by β cells in the pancreas.
Exam Tips
Key Definitions to Remember
- Homeostasis
- Negative Feedback
- Osmoregulation
- Deamination
- Nephron
- Glucagon
- Insulin
Common Confusions
- Confusing osmoregulation with general water balance
- Misunderstanding the role of insulin and glucagon in blood glucose regulation
Typical Exam Questions
- What is homeostasis? Homeostasis is the process of maintaining stable internal conditions in the body.
- How does negative feedback work in regulating blood glucose levels? Negative feedback involves insulin and glucagon adjusting blood glucose levels to maintain balance.
- What role do the kidneys play in osmoregulation? The kidneys regulate water balance by adjusting water reabsorption in response to ADH.
What Examiners Usually Test
- Understanding of negative feedback mechanisms
- The structure and function of the nephron
- The hormonal regulation of blood glucose levels