feedback systems

Question 1

The role of the hormone adrenaline in the body

Answer 1

1.Produced by adrenal glands in times of fear/stress
2.Increasing heart rate to boost delivery of oxygen & glucose to the brain&muscles
3.More energy released via respiration
4.To prepare body for fight or flight

Question 2

role of the hormone thyroxine in the body

Answer 2

1.Released from thyroid gland
2.Stimulates BMR
3.Plays an important role in growth&development

Question 3

Describe what happens in negative feedback

Answer 3

1.Receptors detect levels too low/high
2. Effectors respond to counteract change
3.Levels restored to normal/original

Question 4

Describe how thyroxine is controlled by negative feedback (levels in blood lower than normal)

Answer 4

1.Pituitary gland secretes more TSH
2.Stimulating thyroid to release more thyroxine
3.Levels in blood rise to normal

Question 5

Describe how thyroxine is controlled by negative feedback (levels in blood higher than normal)

Answer 5

1.Thyroxine inhibits TSH from pituitary gland
2.Less thyroxine released from thyroid gland
3.Levels in blood descrease back to normal