The Endocrine System and Fight or Flight

Question 1

Why is an increase in the release of clotting factors into the bloodstream a choice during fight or flight?

Answer 1

Increased the release of clotting factors into the bloodstream = better healing response to injury.

Question 2

Why is a decrease in salivation a choice during fight or flight?

Answer 2

Salivation decreases = allows more oxygenated blood to working muscles.

Question 3

Why is pupil dilation a choice during fight or flight?

Answer 3

Pupils dilate = more light able to enter pupils, allowing the host to see more efficiently.

Question 4

Why is an increase in breathing rate a choice during fight or flight?

Answer 4

Breathing rate increases = more oxygen available.

Question 5

Why is perspiration increasing a choice during fight or flight?

Answer 5

Perspiration increases = releases heat (evaporation).

Question 6

Why is muscles tensing a choice during fight or flight?

Answer 6

Muscles tensing = preparation for movement/ contraction.

Question 7

Why is decreased digestion a choice during fight or flight?

Answer 7

Decreased digestion = allows more oxygenated blood to be focused to working muscles.

Question 8

Why are increases in blood pressure and heart rate a choice during fight or flight?

Answer 8

Increases in blood pressure and heart rate = increases oxygen supply in muscles.

Question 9

What is cortisol? What produces it?

Answer 9

A glucocorticoid produced by the adrenal cortex. It is known as the ‘stress’ hormone.

Question 10

What does ACTH stand for? What is it?

Answer 10

ACTH: Adrenocorticotrophic hormone. Secreted by the anterior pituitary gland and stimulates the adrenal cortex.

Question 11

What does CRF stand for? What is it?

Answer 11

Corticotrophin-releasing factor: A hormone released by the hypothalamus, stimulates the anterior pituitary gland.

Question 12

Outline the process of HPAC.

Answer 12

If exposed to a stressor for several hours or more, this pathway will kick in otherwise SAM will use up bodily resources. As a result, there is a counter-shock response designed to minimise any damage that may be caused. The hypothalamus releases hormones (such as corticotrophin-releasing factor, (CRF)) that stimulates the anterior pituitary gland. The anterior pituitary gland secretes the adrenocorticotrophic hormone (ACTH). ACTH stimulates the adrenal cortex. The adrenal cortex produces various glucocorticoids such as cortisol (the ‘stress’ hormone). This has an effect on glucose metabolism.

Question 13

What does HPAC stand for?

Answer 13

HPAC: Hypothalamic-Pituitary-Adrenocortical Axis

Question 14

Outline the process of the SAM.

Answer 14

Activity in the sympathetic branch of the ANS stimulates the adrenal medulla, which forms part of the adrenal glands.

The adrenal medulla secretes the hormones adrenaline and noradrenaline.

These hormones lead to increased arousal of the sympathetic nervous system and reduced activity in the parasympathetic nervous system.

E.g. increased heart rate, increased breathing rate, decreased salivation.

Question 15

What does SAM stand for?

Answer 15

SAM: Sympathetic Adrenal Medullary Pathway

Question 16

What 2 processes are triggered during fight or flight? What do these trigger?

Answer 16

The hypothalamus (a small gland in the brain) releases a hormone to trigger activity in the sympathetic nervous system.

The sympathetic branch stimulates the adrenal medulla (part of the adrenal gland that sits just on top of the kidney) and this secretes adrenaline and noradrenaline into our bloodstream.

These hormones trigger physical effects on the body.

Question 17

What must happen for fight or flight to ‘kick in’?

Answer 17

Your ANS needs to change itself from a resting stage (parasympathetic state) to the physiologically aroused (sympathetic state).

Question 18

State the characteristics as how the endocrine system influences behaviour.

Answer 18

Endocrine system: slower, long span time, uses blood, controls indirectly.

Question 19

State the characteristics as how the nervous system influences behaviour.

Answer 19

Nervous system: faster, shorter span time, uses nerves, controls directly.

Question 20

What is the endocrine system?

Answer 20

A series of ductless glands which secrete chemicals (hormones) throughout the body via the bloodstream. A communication system for the organs of the body.