Homeostasis Flashcards
Define homeostasis
The maintenance of a stable internal environment within a set range despite a changing external environment and varying internal activity using negative feedback mechanisms
What is the normal physiological range for body temp?
36.1-38
What is the normal physiological range for heart rate?
51-90 BPM
What is the normal physiological range for breathing rate?
12-20 breaths per min
What is the normal physiological range for blood O2 saturation?
96-100%
What is a negative feedback loop?
If the value of the regulated system is disturbed, the system functions to restore it towards its set point value
What does the medulla oblongata control?
- Breathing
- Heart rate
- Blood pressure
- Chemo-sensors for CO2
What does the hypothalamus control?
- temperature
- water balance (through ADH)
What are the main three factors that are regulated?
- thermoregulation
- chemoregulation
- glucoregulation
How does hypoglycaemia affect the body?
- affects CNS
- can lead to confusion, fatigue, seizure, coma, death
How does hyperglycaemia affect the body?
- damages microvasculature (eyes, kidneys, nerves)
- damages macrovasculature (lining of large blood vessels)
What is positive feedback?
Magnifies the original response instead of correcting it (e.g. clotting after wound, cervical stretching in childbirth)