Adrenaline and Thyroxine

Question 1

Adrenaline is a ______ produced by the __________

Answer 1

hormone - adrenal glands

Question 2

When is adrenaline produced?

Answer 2

during the ‘fight or flight’ response - when you get scared, stressed or need to exercise. It prepares the body to act quickly.

Question 3

Effects of adrenaline?

Answer 3

1. increase heart rate
2. increase blood pressure
3. increase blood flow to muscles
4. increases blood glucose levels, by stimulating the liver to break down glycogen into glucose and release it into the bloodstream.

Question 4

Thyroxine is a __________ produced by the ________ ________

Answer 4

hormone - thyroid gland

Question 5

what does thyroxine do?

Answer 5

Increases metabolic rate - also has other roles with growth and development but this is the main function

Question 6

How is the production of thyroxine regulated? How is it a negative feedback system?

Answer 6

The pituitary gland produces TSH, a hormone that stimulates the release of thyroxine.

In turn, thyroxine inhibits the production of TSH.

1.
If thyroxine levels are too low - the pituitary gland will release TSH. This then stimulates the thyroid gland to release more thyroxine. So thyroxine levels in the blood increase back up to normal.

2.
If thyroxine levels are too high - the thyroxine will inhibit the pituitary gland from producing TSH. Less TSH means that the thyroid gland won’t release as much thyroxine. So thyroxine levels in the blood fall back to normal.