Hormones and homeostasis

Question 1

List the glands part of the endocrine system

Answer 1

1. pituitary gland- the base of the brain
2. thyroid gland- produces thyroxine
3. Pancreas- produces insulin
4. Adrenal gland- produces adrenaline
5. Testes- produces testosterone
6. Ovaries- produce oestrogen

Question 2

describe adrenaline

Answer 2

• produced in the adrenal gland
• prepares body for fight or flight response
• increases heart and breathing rate, dilates pupils

Question 3

describe insulin

Answer 3

• produced in pancreas
• lowers blood glucose levels
• causes excess glucose in the blood to be taken up by the muscles and liver and converted into glycogen for storage

Question 4

describe testosterone

Answer 4

• produced in the testes
• male sex organs
• development of secondary sexual characteristics in males

Question 5

describe oestrogen

Answer 5

• produced in ovaries
• main sex hormone in females
• development of secondary sexual characteristics in females and controls menstrual cycle

Question 6

what does adrenaline do in general

Answer 6

1. increases blood glucose concentration for increased respiration in muscle cells
2. increases pulse and breathing rate so glucose and oxygen can be delivered to muscle cells and carbon taken away from muscles very fast
3. diverting blood flow towards muscles and away from non-essential parts of the body such as the alimentary canal
4. dilates pupils to allow as much light as possible to enter to reach retina

Question 7

explain how negative feed back works

Answer 7

if the level of something rises, control systems are switched on to reduce it again
if the level of something falls control systems are switched on to increase it again. it is usually a continuous cycle of bringing levels down and bringing them up again