Hormonal control

Question 1

What is the function of the endocrine system?

Answer 1

Uses hormones to send info about changes in environment around the body to bring about a designated response

Question 2

What is the role of hormones?

Answer 2

Act as chemical messengers binding to specific receptors on target cells

Question 3

Describe how hormones act as chemical messengers?

Answer 3

1) hormones are produced by endocrine gland cells
2) when stimulated glands release hormones into bloodstream
3) blood carries hormones to their target cells
4) they attach to receptors on or inside target cells
5) cells then respond to hormones

Question 4

What are the 2 types of hormones?

Answer 4

Non-steroid = peptide hormones
Steroid = lipid soluble hormones

Question 5

Describe the action of non-steroid hormones?

Answer 5

• can’t diffuse across phospholipid bilayer as hydrophilic
• bind to receptors on cell-surface membrane of target cells to activate 2nd messengers

Question 6

Describe the action of steroid hormones?

Answer 6

• can diffuse across phospholipid bilayer as hydrophobic
• bind to receptor molecules in cytoplasm or nucleus forming a hormone-receptor complex acting as transcription factor

Question 7

What are examples of steroidal hormones?

Answer 7

• oestrogen

Question 8

What are examples of non-steroidal hormones?

Answer 8

• adrenaline
• noradrenaline

Question 10

What are the differences between the endocrine and nervous system?

Answer 10

• endocrine signals via hormones nervous via nerve impulses
• endocrine transmit via blood nervous via neurones
• endocrine have slow speed nervous have rapid
• endocrine wide spread nervous localised
• endocrine longterm effect nervous short term

Question 11

What is the location and structure of the adrenal glands?

Answer 11

Location = triangular endocrine glands located above each kidney

Structure = consists of 2 main regions surrounded by a capsule

Question 12

What are the 2 main regions of the adrenal glands?

Answer 12

Adrenal cortex = outer region of the glands responsible for producing vital steroid hormones

Adrenal medulla = inner region at the center of the glands known for producing non-steroidal hormones

Question 13

What is the function of glucocorticoids and give an example?

Answer 13

Function = regulate metabolism, controls blood pressure and stress response and suppresses inflammation

E.g = cortisol and corticosterone

Question 14

What is the function of mineralocorticoids and give an example?

Answer 14

Function = maintain blood pressure by balancing salt and water in the blood and body fluids

E.g = aldosterone

Question 15

What is the function of androgens and give an example?

Answer 15

Function = regulation of sexual characteristics and cell growth

E.g testosterone

Question 16

How is the release of hormones from the adrenal cortex regulated?

Answer 16

regulated by chemical signals from the hypothalamus and kidneys

Question 17

What does the adrenal medulla produce and when?

Answer 17

Produces = catecholamines (non steroidal hormones)

When = prepare the body for stressful or dangerous situations when the body’s stimulated by the SNS

Question 18

What are the main affects of adrenaline?

Answer 18

• dilated bronchioles
• increased BR
• increased blood glucose levels
• increased HR and BP increasing blood flow to the muscles and brain

Question 19

What are the main affects of noradrenaline?

Answer 19

• increased HR
• expands air passages
• dilates pupils
• vasoconstriction of non-essential organs