Lesson 4

Question 1

Endocrine System

Answer 1

• The endocrine system provides a chemical system of communication in the body via the blood stream.
• Endocrine glands produce and secrete hormones into the bloodstream which are required to regulate many bodily functions.
• The major glands of the endocrine system include the pituitary gland and the adrenal glands.
• Each gland produces different hormones which regulate activity of organs/tissues in the body.

Question 2

Target Cells

Answer 2

• Although hormones come into contact with most cells
  in the body, they only affect a limited number of cells, known as target cells.
• Target cells respond to a particular hormone because they have receptors for that hormone.
• When enough receptor sites are stimulated by that hormone there is a physiological reaction.

Question 3

Pituitary Gland

Answer 3

• The pituitary gland is located in the brain.
• It produces hormones whose primary function is to influence the release of other hormones from other glands in the body.
• The pituitary gland is controlled by the hypothalamus, a region of the brain just above the pituitary gland.

Question 4

Hypothalamus

Answer 4

• The hypothalamus receives information from many sources about the basic functions of the body. - The hypothalamus then sends a signal to the pituitary gland in the form of a releasing hormone.
• This causes the pituitary gland to send a stimulating hormone into the bloodstream to tell the target gland to release its hormone.
• As levels of this hormone rise in the bloodstream the hypothalamus shuts down production of the releasing hormone and the pituitary gland shuts down secretion of the stimulating hormone

Question 5

The anterior pituitary gland

Answer 5

Releases the hormone called ACTH which is responsible for preparing the body for the fight or flight response which occurs when someone is stressed.

Question 6

The posterior pituitary gland

Answer 6

Responsible for releasing the hormone oxytocin which is crucial for infant/mother bonding.

Question 7

Adrenal Cortex

Answer 7

• The outer section of the adrenal gland is called the adrenal cortex.
• It produces the hormone cortisol which is produced in high amounts when someone is chronically (long-term) stressed.
• Cortisol is also responsible for the cardiovascular system, for instance it will increase blood pressure and causes blood vessels to contract.

Question 8

Adrenal Medulla

Answer 8

• The inner section of the adrenal gland is called the adrenal medulla which produces adrenaline the hormone that is needed for the fight or flight response that is activated when someone is stressed.
• Adrenaline is responsible for increasing heart rate, dilating pupils and stopping digestion.