BIO 03 - Endocrine system

Question 1

What is the endocrine system?

Answer 1

• One of the body’s major information systems that instructs glands to release hormones directly into the blood stream
• These hormones are carried towards target organs in the body
• Communicates via chemicals

Question 2

What is the pituitary gland?

Answer 2

• They key endocrine gland is the pituitary gland, located in the brain
• It is often called the ‘master gland’ because it controls the release of hormones from all the other endocrine glands in the body

Question 3

What is a gland?

Answer 3

An organ in the body that synthesises substances such as hormones

Question 4

What is a hormone?

Answer 4

• Chemical substances that circulate in the bloodstream and only affect target organs
• They are produced in large quantities but disappear quickly
• Their effects are very powerful

Question 5

What is the fight or flight response?

Answer 5

• The way an animal response when stressed
• The body becomes physiologically aroused in readiness to fight an aggressor or, in some cases, flee

Question 6

What is adrenaline?

Answer 6

• A hormone produced by the adrenal medulla (a part of the adrenal gland lying near your kidney) which is part of the human body’s immediate stress response system
• Adrenaline has a strong effect on the cells of the cardiovascular system – stimulating heart rate, contracting blood vessels and dilating air passages

Question 7

What is the main hormone produced by the pituitary gland, adrenal gland, ovaries and testes?

Answer 7

• Pituitary => ACTH
• Adrenal gland => adrenaline
• Ovaries => oestrogen
• Testes => testosterone

Question 8

What effect does the pituitary gland have?

Answer 8

• It is the master gland
• It stimulates adrenal cortex and release of cortisol during stress response and adrenal medulla to release adrenaline

Question 9

What effect does the adrenal gland have?

Answer 9

• Key hormone in fight or flight response
• Causes physiological changes in the body

Question 10

What effect do the ovaries have?

Answer 10

Regulates female reproductive system

Question 11

What effect do the testes have?

Answer 11

Development of male sex characteristics, muscle growth and aggression

Question 12

Compare the endocrine and nervous system?

Answer 12

Endocrine system:
Medium of signalling => Chemical signalling (hormones produced by glands)
Speed of transmission => Slow (seconds; travels through the bloodstream)
Duration of effects => Affects last for a long period of time – long lived (until hormone breaks down)

Nervous system:
Medium of signalling =>
Electrical signalling (electrical impulses travel along neurones but it is chemical across synapse)
Speed of transmission => Fast (milliseconds; neurons are interconnected)
Duration of effects => Short-lived affects (until neural impulse ceases)