Biopsychology - The Endocrine System

Question 1

What is the endocrine system and what does it do?

Answer 1

• The function for the whole endocrine system is to produce different hormones which regulate the activity of the organs and tissues in the body
• It works along side the nervous system to control vital functions in the body.
• It works at a slower rate than the nervous system
• It is a series of glands that produce and release bodily chemicals known as hormones
• The endocrine system uses blood vessels to deliver hormones to their target sites instead of nerve cells

Question 2

Explain endocrine glands

Answer 2

• They produce and secrete hormones that regulate the activity of cells or organs in the body
• They include the pituitary, adrenal and reproductive organs
• A signal is sent from the hypothalamus to the pituitary gland to release a stimulating hormone into the bloodstream, the stimulating hormone then signals the target gland to secrete the hormone. As this level of hormone increases in the bloodstream, the hypothalamus shuts down secretion of the stimulating hormone. This slows down secretion of the target glands hormone which results in stable concentrations of hormones ciculating in the bloodstream.

Question 3

Explain hormones

Answer 3

• They are chemicals that ciculate in the bloodstream and are carried to target cells in the body
• The target cells respond to the hormone as they have receptors for that hormone
• When enough receptor sites have been stimulated by hormones, it results in a physiological change in the body
• The timing of hormones being released is very important as well as the amount
• Too much or too little at the wrong time can result in bodily systems not working properly
• For example, too much cortisol can lead to Cushing’s syndrome which can result in depression or high blood pressure

Question 4

Explain the pituitary gland

Answer 4

• It is located in the brain and is known as the master gland
• It’s function is to influence the release of hormones from the other glands and to regulate the functioning of all the other glands
• High levels of hormones produced in other endocrine glands can stop the hypothalamus and pituitary releasing more of their own hormone - this is called negative feedback: it prevents hormone levels rising too high

Question 5

Explain the adrenal glands

Answer 5

• They are located just above the kidneys
• Their function is to produce the stress hormones adrenaline and cortisol
• Adrenaline function: prepare body to deal with stressors, it provides the body with a burst of energy, increased heart rate etc
• Cortisol function: help body deal with stressors, has anti inflammatory functions, it increases our blood sugar and decreases sensitivity to pain

Question 6

Explain the testes

Answer 6

• Function - control release of testosterone and producing sperm
• Testosterone function - cause development of male characteristics such as facial hair growth, deepening of voice and a growth spurt during pubity
• Testosterone also has a role in mental functioning, regulating mood and sex drive

Question 7

Explain the ovaries

Answer 7

• Their function is to produce eggs and the hormones oestrogen and progesterone
• Progesterone function - facilitate woman’s pregnancy and is associated with increased sensitivity to social issues. It helps identify social threats.
• Oestrogen function - bone strenghtening, prevents heart disease and regulates menstrual cycle