The Endocrine System

Question 1

Explain the function of the endocrine system

Answer 1

• Works alongside the nervous system to control vital functions in the body.
• It secretes the hormones required to regulate many bodily functions, providing a chemical system of communication via the bloodstream.

Question 2

What are the 6 glands?

Answer 2

1) Pituitary gland.
2) Adrenal gland.
3) Thyroid gland.
4) Pineal gland.
5) Testes
6) Ovaries

Question 3

What are the glands and their hormones?

Answer 3

1) Pituitary gland= oxytocin.
2) Adrenal gland= adrenaline.
3) Thyroid gland= thyroxine.
4) Pineal gland= melatonin.
5) Testes= testosterone.
6) Ovaries= oestrogen.

Question 4

What is the function of the pituitary gland?

Answer 4

• Some of the hormones released are important for regulating the endocrine system, hence the nickname ‘master gland’.
• The Pituitary gland releases oxytocin, thought to be important for reproductive behaviour.

Question 5

What is the function of the adrenal gland?

Answer 5

• An important part of of the fight or flight response as it facilitates the release of adrenaline.

Question 6

What is the function of the thyroid gland?

Answer 6

• Produces thyroxine.
• This hormone affects cells in the heart (increases heart rate) + also affects metabolic rates which in turn affects growth rate.

Question 7

What is the function of the pineal gland?

Answer 7

• Produces melatonin which affects the regulation of arousal, biological rhythms and the sleep-wake cycle.

Question 8

What is the function of the testes?

Answer 8

• They enable the release of testosterone (male hormone) responsible for the development of male secondary sexual characteristics at puberty.
• Also promote muscle mass and muscle growth.

Question 9

What is the function of the ovaries?

Answer 9

• They enable the release of oestrogen and progesterone (female hormone), regulates menstrual cycle and pregnancy.

Question 10

The pituitary gland (more info)

Answer 10

• “Master gland”
• Many of the hormones released by the pituitary gland control the secretion of other endocrine glands (rather than having a direct effect on cells + tissues in the body).
• The release of hormones from the pituitary gland in turn is controlled by the hypothalamus.
• The hypothalamus can therefore be seen to control and regulate the endocrine system in general.

Question 11

The adrenal gland (more info)

Answer 11

• Plays an important part in the fight or flight response as it facilitates the release of adrenaline.

Question 12

What is the role of adrenaline?

Answer 12

• Adrenaline is released by the adrenal medulla in response to the activation of the sympathomedullary pathway (sympathetic adrenomedullary pathway).

Question 13

What is the SAM pathway?

Answer 13

1) The hypothalamus recognises that there is a threat (it sends a message to….).
2) The adrenal gland (specifically the adrenal medulla)- this triggers the release of….
3) Adrenaline to endocrine system + noradrenaline in the brain (this prompts physiological changes).

Question 14

What are the 6 effects of adrenaline?

Answer 14

1) Slows digestion.
2) Dry mouth.
3) Increased HR.
4) Vision.
5) Sweat.
6) Muscle tension.

Question 15

Slows digestion- fight or flight response.

Answer 15

• Slows digestion to save energy for prioritised functions (e.g. running).

Question 16

Dry mouth- fight or flight response.

Answer 16

• Inhibits salivary glands, causing a dry mouth.

Question 17

Increased HR- fight or flight response.

Answer 17

• Heart rate increases to speed up the blood flow to vital organs and improve the spread of adrenaline around the body.

Question 18

Vision- fight or flight response.

Answer 18

• Pupils dilate to improve vision.

Question 19

Sweat- fight or flight response.

Answer 19

• Increased production of sweat to facilitate temperature regulation.

Question 20

Muscle tension- fight or flight response.

Answer 20

• Muscles become tense to improve reaction time and speed.