Negative Feedback

Question 1

What is the role of negative feedback?

Answer 1

Negative feedback systems to maintain a steady state

If a factor in internal environment changes, other changes take to restore it to the original level

Question 2

What hormones are involved in negative feedback systems?

Answer 2

Insulin and glucogon in pancreas
Most female sex hormones
Thyroxine in the thyroid gland

Question 3

How does the thyroxine and negative feedback work?

Answer 3

Thyroid gland uses iodine for your diet to make thyroxine
Thyroxine controls basal metabolic rate
Thyroxine important in growth and development
Levels of thyroxine kept stable by negative feedback
Pituitary gland produces TSH and with thyroxine maintains stable levels,
in the body

Question 4

Adrenaline and non negative feedback

Answer 4

Produced in times of fear or stress
Increases heart rate and boosts delivery of blood and glucose to brain and muscles preparing body for fight or flight
Causes:
1. Heart and breathing to increase stored glycogen (liver) to convert into glucose for respiration
2. Pupils to dilate to let in more light
3. Increased mental awareness
4. Divert blood away from digestive system to limb muscles
Once danger over raised levels of awareness not needed and adrenal gland stops releasing adrenaline and systems return to normal
NOT A NEGATIVE FEEDBACK LOOP