Biopsychology: The Function of the Endocrine System

Question 1

What are the two functions of the endocrine system?

Answer 1

1. The endocrine system functions to secrete hormones in the bloodstream to regulate many of our bodily functions.
   - For example, the endocrine system releases melatonin from the pineal gland that induces sleepiness and relaxation.
   - Together with the nervous system, they work closely together to regulate and coordinate physiological processes in the human body but work very differently.
2. The endocrine system also functions to provide a chemical system of communication via the bloodstream.
   - It’s a network of glands spread throughout the body that manufacture and secrete chemical messengers known as hormones throughout the body. For example, the adrenal glands release adrenaline which instigates the stress response.
   - Hence, the endocrine system does not use nerves to transmit information; rather they use blood vessels to deliver hormones to their target sites throughout the body.

Question 2

Hormones are defined as…

Answer 2

Chemicals messengers that are released from glands (e.g. adrenal glands; ovaries) that circulate in the bloodstream and are carried to target structures around the body.

Each hormone will ‘excite’ / stimulate a particular part of the body.

This will usually lead to the release of other hormones.

Question 3

Name and describe the ‘master gland’

Answer 3

The gland that exerts the most influence is called the ‘pituitary gland’.
This gland has the power to influence all other endocrine glands, and so sometimes it is called the master gland.
It is governed by a powerful area of the brain called the hypothalamus.
This is the CNS main link to the endocrine system.

Question 4

What is adrenocortical trophic hormone?

Answer 4

Adrenocortical trophic hormone (ACTH)
Produced by the (anterior) pituitary gland.
ACTH stimulates the release of glucocorticoids, such as cortisol (your body’s main stress hormone), from the adrenal cortex.
It is a key component in the stress response.

Question 5

What is prolactin?

Answer 5

Produced by the (posterior) pituitary gland.
Important in promoting uterine contractions and lactation.