5.4 Hormonal Communication

Question 1

What are endocrine glands?

Answer 1

Specialised group of cells to secrete hormones directly into blood without a duct

Question 2

What are hormones?

Answer 2

Chemical messengers secreted by endocrine glands, and can be steroid or non-steroid.

Question 3

What are target cells?

Answer 3

Cells that have specific receptors for a hormone that the hormone needs to act on.

Question 4

What can stimulate a gland to secrete a hormone?

Answer 4

A change in conc of another chemical, or action potentials.

Question 5

What happens after a non-steroid hormone binds to a receptor on the cell surface membrane?

Answer 5

A G protein activates an enzyme in the cell surface membrane.

Question 6

What is the first messenger?

Answer 6

The non-steroid hormone because it carries a chemical message from an endocrine gland to the target cell receptor.

Question 7

What is the second messenger?

Answer 7

The signalling molecule, because it carries the chemical message from the receptor to the other parts of the cell.

Question 8

What does the 2nd messenger do?

Answer 8

They activate an enzyme cascade in the cell.

Question 9

What is a target cell for adrenaline?

Answer 9

Hepatocyte

Question 10

What enzyme catalyses the reaction of ATP > cAMP ?

Answer 10

Adenylyl cyclase

Question 11

What does a G protein do?

Answer 11

Activate a membrane bound enzyme after a hormone has bound to a receptor.

Question 12

What type of gland is the adrenal gland?

Answer 12

Endocrine

Question 13

What is the outer part of the adrenal gland called?

Answer 13

Cortex

Question 14

What is the inner part of the adrenal gland called?

Answer 14

Medulla

Question 15

What type of hormones does the adrenal cortex secrete?

Answer 15

Steroid hormones

Question 16

Why can steroid hormones directly affect DNA and protein synthesis?

Answer 16

They can diffuse through the lipid bilayer into the cell and nucleus.

Question 17

Where is aldosterone secreted from?

Answer 17

Adrenal cortex

Question 18

What does aldosterone do?

Answer 18

Maintains blood pressure

Question 19

How is blood pressure maintained?

Answer 19

Aldosterone increases uptake of Na+ and water, increasing blood volume and pressure.

Question 20

What type of hormone can suppress the immune system?

Answer 20

Adrenal cortex steroid hormones

Question 21

Where is cortisol secreted from?

Answer 21

Adrenal cortex

Question 22

What does cortisol do?

Answer 22

• Controls metabolism of proteins, fats and carbs into glucose.
• Helps development of sexual charecteristics

Question 23

Why is cortisol released in response to stress?

Answer 23

Controls metabolism to make glucose and energy more available so brain and muscles can coordinate response to stress.

Question 24

What type of hormone is released from the adrenal medulla?

Answer 24

Non steroid hormones

Question 25

What hormones are released from the adrenal cortex?

Answer 25

Cortisol and aldosterone

Question 26

What hormones are released from the adrenal medulla?

Answer 26

Adrenaline and noradrenaline

Question 27

What are catecholamines?

Answer 27

Amino acid derivative hormones

Question 28

How does adrenaline increase breathing depth?

Answer 28

Relaxes smooth muscle in bronchioles

Question 29

What is adrenaline’s primary function?

Answer 29

To make more energy available in the short term to prepare the body for action.

Question 30

What is hypoglycemia?

Answer 30

Not enough glucose delivered to tissues

Question 31

What is hyperglycemia?

Answer 31

Blood glucose too high for too long

Question 32

What cells moniter blood glucose concentration?

Answer 32

Islets of langerhans

Question 33

What are the target cells of insulin and glucagon?

Answer 33

Hepatocytes in liver

Question 34

What cells secrete insulin?

Answer 34

Beta cells

Question 35

What cells secrete glucagon?

Answer 35

Alpha cells

Question 36

Where are alpha and beta cells found?

Answer 36

Cell clusters in islets of langerhans

Question 37

What is glucagon?

Answer 37

A non steroid hormone which acts to raise blood glucose concentration

Question 38

What is insulin?

Answer 38

A non steroid hormone which acts to lower blood glucose concentration

Question 39

What is glycogenesis?

Answer 39

Glucose converted to glycogen

Question 40

What is glycogenolysis?

Answer 40

Glycogen converted to glucose

Question 41

What is gluconeogenesis?

Answer 41

Amino acids/fats converted to glucose

Question 42

What is the difference between exocrine and endocrine glands?

Answer 42

Exocrine glands have ducts and endocrine are ductless.