Homeostasis

Question 1

Define homeostasis

Answer 1

The maintenance of a stable internal environment within a set range despite a changing external environment and varying internal activity using negative feedback mechanisms

Question 2

What is the normal physiological range for body temp?

Answer 2

36.1-38

Question 3

What is the normal physiological range for heart rate?

Answer 3

51-90 BPM

Question 4

What is the normal physiological range for breathing rate?

Answer 4

12-20 breaths per min

Question 5

What is the normal physiological range for blood O2 saturation?

Answer 5

96-100%

Question 6

What is a negative feedback loop?

Answer 6

If the value of the regulated system is disturbed, the system functions to restore it towards its set point value

Question 7

What does the medulla oblongata control?

Answer 7

1. Breathing
2. Heart rate
3. Blood pressure
4. Chemo-sensors for CO2

Question 8

What does the hypothalamus control?

Answer 8

1. temperature
2. water balance (through ADH)

Question 9

What are the main three factors that are regulated?

Answer 9

1. thermoregulation
2. chemoregulation
3. glucoregulation

Question 10

How does hypoglycaemia affect the body?

Answer 10

1. affects CNS
2. can lead to confusion, fatigue, seizure, coma, death

Question 11

How does hyperglycaemia affect the body?

Answer 11

1. damages microvasculature (eyes, kidneys, nerves)
2. damages macrovasculature (lining of large blood vessels)

Question 12

What is positive feedback?

Answer 12

Magnifies the original response instead of correcting it (e.g. clotting after wound, cervical stretching in childbirth)