14.1 Hormonal Communication

Question 1

What is an endocrine gland?

Answer 1

A group of cells which are specialised to secrete chemicals directly into the bloodstream.

Question 2

What is the role of the pituitary gland?

Answer 2

Produces:
Growth hormone
Anti-diuretic (AD) hormone (reabsorption of water into kidneys
Gonadotrophins (development of ovaries and testes)

Question 3

What is the role of the thyroid gland?

Answer 3

Produces thyroxine

Question 4

What does thyroxine do?

Answer 4

Controls:
Rate of metabolism
Rate that glucose is used up in respiration
Promotes growth

Question 5

What is the role of the adrenal gland?

Answer 5

Produces adrenaline

Question 6

What does adrenaline do?

Answer 6

Increase:
Heart rate
Breathing rate
Blood sugar

Question 7

What is the role of the testis?

Answer 7

Produces testosterone

Question 8

What does testosterone do?

Answer 8

Controls sperm production and secondary characteristics

Question 9

What is the role of the pineal gland?

Answer 9

Produces melatonin

Question 10

What does melatonin do?

Answer 10

Helps control:
Reproductive development
Daily cycles

Question 11

What is the role of the thymus?

Answer 11

Produces thymosin

Question 12

What does thymosin do?

Answer 12

Promotes production and maturation of white blood cells

Question 13

What is the role of the pancreas?

Answer 13

Produce insulin and glucagon

Question 14

What does insulin do?

Answer 14

Convert excess glucose into glycogen (in the liver).

Question 15

What does glucagon do?

Answer 15

Convert glycogen into glucose (in the liver).

Question 16

What do the ovaries do?

Answer 16

Produces oestrogen and progesterone

Question 17

What does oestrogen do?

Answer 17

Control ovulation and secondary sexual characteristics

Question 18

What does progesterone do?

Answer 18

Controls ovulation and secondary sexual characteristics
Prepares the uterus lining for receiving an embryo

Question 19

How does the endocrine system secrete hormones?

Answer 19

Secrets hormones directly into the bloodstream

Question 20

How does the exocrine system secrete chemicals?

Answer 20

Through ducts into organs/ the surface of the body

Question 21

Name 6 places hormones derive from.

Answer 21

Hormones can be steroids, proteins, glycoproteins, polypeptides, amines or tyrosine derivatives.

Question 22

How do hormones get to the target cells to produce a response?

Answer 22

Secreted into the blood
Into the blood plasma
Diffuses out of the blood
Bonds to specific receptors found on membranes/cytoplasm
The target cells produce a response

Question 23

Steroid hormones are lipid soluble, what does this mean they can do?

Answer 23

Pass through lipid component of cell membrane and bind to steroid hormone receptors

Question 24

Where are the steroid hormone receptors in the cell?

Answer 24

In the nucleus and cytoplasm

Question 25

What do hormone-receptor complexes do?

Answer 25

Hormone-receptor complexes that can either facilitate or inhibit transcription of a specific gene

Question 26

Are non steroid hormones hydrophobic or hydrophilic?

Answer 26

Hydrophilic

Question 27

Non steroid hormones can not pass through the cell membrane, so how do they affect the cells?

Answer 27

Bind to receptors in cell surface membrane if target cell,
This triggers a cascade reaction mediated by chemicals aka secondary messengers like adrenaline.

Question 28

Describe 4 differences between the hormonal and neuronal systems.

Answer 28

H- uses hormones
N- uses nerve impulses

H- hormones are directly released into the bloodstream
N- transmissions via neurones

H- hormones are not broken down as quickly so they are long lasting and wide spread
N- neurotransmitters are transmitted and broken down quickly, so they are specific and short lived

H- hormones can be permanent and irreversible
N- they are temporary and reversible

Question 29

What are the two parts of the adrenal gland?

Answer 29

Adrenal cortex
Medulla

Question 30

What does the adrenal cortex do?

Answer 30

Produces essential hormones, e.g. aldosterone and cortisol

Question 31

What does the adrenal medulla do?

Answer 31

Produce non-essential hormones

Question 32

How is the adrenal cortex controlled?

Answer 32

By hormones from the pituitary gland.

Question 33

What are the three types of hormones produced by the adrenal cortex?

Answer 33

Glucocorticoids
Mineralocorticoids
Androgens

Question 34

Give an example of a glucocorticoid.

Answer 34

Cortisol

Question 35

What does cortisol do?

Answer 35

Helps regulate:
Metabolism (by controlling how the body converts fats proteins and carbohydrates into energy)
Regulate blood pressure

Question 36

What is the hormone that works with cortisol?

Answer 36

Corticosterone

Question 37

What does corticosterone do?

Answer 37

Works with cortisol to regulate immune response and suppress inflammatory reactions.

Question 38

What is an example of a mineralocorticoid?

Answer 38

Aldosterone

Question 39

What does aldosterone do?

Answer 39

Helps control blood pressure by maintaining balance between salt and water concentration in body fluids.

Question 40

What do androgens do?

Answer 40

Cause a small amount of sex hormones to be released.

Question 41

What hormones are released from the adrenal medulla when the body is stressed, and what do they do?

Answer 41

Adrenaline:
Increase heart rate
Increase blood glucose concentration levels by conveying glycogen to glucose (in the liver)

Noradrenaline:
Works with adrenaline to increase heart rate
Widens pupils
Widens air passages in lungs
Narrows blood vessels in non-essential organs

Question 42

What is the ductless gland?

Answer 42

Another name does the endocrine gland