Homeostasis Flashcards
1
Q
How is the ECF divided?
A
80% is interstitial fluid (ISF)
20% is Plasma
2
Q
Explain how a negative feedback control works?
A
- Change in value (e.g. temp) detected by receptors
- Data fed to integrating centre
- Compared to reference level
- If different, a signal is sent to an effector
- Change is negated
3
Q
What is the magnitude of the error signal proportional to? (-ve feedback)
A
The magnitude of the error signal is proportional to the size of deviation
4
Q
Example of negative feedback?
A
Core body temp rises Fed to integrating centre Error signal fired capillaires vasodilate & sweat glands activate Core Body temp returns to normal
5
Q
What is feed forward control?
A
Similar to negative feedback but with more sensors so changes be anticipated & negated in advance
E.g. our skin detecting temp changes before they affect our core body temp
6
Q
How much of body water is in the ICF?
A
66% of body water (28L) in intracellular fluid
7
Q
How much water is in the ECF?
A
33% of body water (14L) in extracellular fluid.
