Unit4- 5.8~ The concept of homeostasis

Question 1

What is homeostasis?

Answer 1

The process by which the body maintains a stable internal environment, even when external conditions change.

Question 2

What is maintained by homeostasis?

Answer 2

• Temperature
• Oxygen levels
• Water levels
• Tissue Fluid
• Composition

Question 3

Why is homeostasis important?

Answer 3

• Independence: Stopes organisms being reliant on external environment
• Enzymes: Sensitive to pH and temp changes. Big changes could stop reactions occuring
• Blood glucose: Essential to maintain this to maintain water potential and give cells constant supply of glucose for respiration
• Water potential: Changing this in blood/tissue fluid could make cells shrink/burst, preventing them operating normally

Question 4

Control mechanisms

What are the stages of homeostatic control?

Answer 4

• The set point (The norm)
• Receptor (Detects variations)
• Controller (Co-ordinates info and send instructions)
• Effector (Brings about changes)
• Feedback loop (Tells receptor about the changes)