Endocrine System

Question 1

What is meant by the endocrine system?

Answer 1

A network of glands that secrete chemical messages called hormones.

Use hormones to transmit information through blood vessels, instead of neurons.

Question 2

What is a hormone?

Answer 2

A chemical messenger that moves through the bloodstream to bind onto target organs or cells.

Question 3

What are glands?

Answer 3

Organs which secrete hormones, and make up the endocrine system.

Question 4

What is the hypothalamus?

Answer 4

Stimulates and controls the release of hormones from the pituitary gland.

The hypothalamus is the control system which regulates the endocrine system.
Connected to the pituitary gland.

Question 5

Name 6 glands and the hormones they release.

Answer 5

Pituitary gland > adrenocortical trophic hormone & oxytocin

Pineal gland > melatonin

Thyroid gland > thyroxine

Adrenal gland > adrenaline & noradrenaline, and cortisol

Ovaries (female) > oestrogen

Testes (male) > testosterone

Question 6

What is the pituitary gland?

Answer 6

Master gland - releases hormones that control & stimulate the release of hormones from other glands.

Pituitary gland is divided into two lobes.

Question 7

Describe the structure of the pituitary gland. [1 mark]

Answer 7

Divided into 2 lobes…

The anterior lobe

The posterior lobe

which produce different hormones.

Question 8

Name and explain the hormone that is produced from the anterior lobe of the pituitary gland [2 marks]

Answer 8

The anterior lobe releases adrenocortical trophic hormone (ACTH)… (1)

…which stimulates the ADRENAL cortex and the release of CORTISOL, during the stress response. (1)

Question 9

Name and explain the hormone that is produced from the posterior lobe of the pituitary gland [2 marks]

Answer 9

The posterior lobe releases oxytocin… (1)

…which is responsible for uterus contractions during childbirth. (1)

Question 10

Name and explain the hormone that is produced from the pineal gland [2 marks]

Answer 10

The pineal gland releases melatonin… (1)

…which is responsible for important biological rhythms, (e.g. the sleep-wake cycle).

Question 11

Name and explain the hormone that is produced from the thyroid gland [2 marks]

Answer 11

The thyroid gland releases thyroxine… (1)

…which is responsible for regulating metabolism. (1)

Question 12

Describe the structure of the adrenal gland. [1 mark]

Answer 12

Found on top of the kidneys and release hormones in response to stress.

The adrenal gland is divided into 2 parts…

> Adrenal medulla

> Adrenal cortex

Question 13

Name and explain the hormone that is produced from the adrenal medulla [2 marks]

Answer 13

The adrenal medulla releases adrenaline AND noradrenaline… (1)

…which are involved in the fight or flight response. (1)

Question 14

Name and explain the hormone that is produced from the adrenal cortex [2 marks]

Answer 14

The adrenal cortex releases cortisol… (1)

…which stimulates the release of glucose to provide the body with ENERGY suppressing the immune system. (1)

(cortisol is the stress hormone - don’t forget to say “measure cortisol levels” when operationalising the dependent variable of stress)

REMEMBER
“cor”tex and “cor”tisol

Question 15

Name and explain the hormone that is produced from the ovaries in females [2 marks]

Answer 15

The ovaries release oestrogen… (1)

…which controls the regulation of the female REPRODUCTIVE system, including the menstrual cycle and pregnancy.

Question 16

Name and explain the hormone that is produced from the testes in males [2 marks]

Answer 16

The testes release testosterone… (1)

…which is responsible for the development of the male sex characteristics during puberty, while also promoting muscle growth. (1)

Question 17

Explain the two differences between the endocrine system and the nervous system [2 marks]

Answer 17

1= Cells in the ES group into clusters called glands, whereas the cells in the NS are called neurons.

2 = The ES communicates via glands through hormones released into the bloodstream, whereas the NS communicates through electrical signals sent from one neuron to the next.

Question 18

How do glands in the brain receive and send communications?

Answer 18

Glands in the brain RECEIVE electrical signals from neurons, and then SENDS hormones.

Question 19

What is the correct chain of events to describe communication in the endocrine system?

Answer 19

A STIMULUS causes the gland to release a hormone into the bloodstream.

The hormones travel around the bloodstream until they reach TARGET CELLS.

They bind to the RECEPTORS on the target cells.

This causes a RESPONSE in the target cell.

Question 20

Explain how the pituitary gland can control actions in the body via the adrenal glands [4 marks]

Answer 20

The pituitary gland receives electrical signals from neurons in the brain.

In response, pituitary gland releases hormones into the bloodstream.

These hormones act as messengers and travel to other glands in the body, including the adrenal glands.

This communication enables the pituitary gland to control the release of hormones from other glands.

E.G. the pituitary gland tells the adrenal gland to release cortisol and adrenaline in response to stress.

Question 21

Explain how the pituitary gland can control actions in the body via the adrenal glands [4 marks]

Answer 21

The pituitary gland receives electrical signals from neurons in the brain.

In response, pituitary gland releases hormones into the bloodstream.

These hormones act as messengers and travel to other glands in the body, including the adrenal glands.

This communication enables the pituitary gland to control the release of hormones from other glands.

E.G. the pituitary gland tells the adrenal gland to release cortisol and adrenaline in response to stress.