Adrenal Glands

Question 1

What is the role of the adrenal medulla

Answer 1

Homeostasis

Question 2

What does the adrenal medulla secrete

Answer 2

Adrenaline

Noradrenaline

(both hormones)

Question 3

What are the two major structure of the adrenal glands

Answer 3

Outer adrenal cortex

Inner adrenal medulla

Question 4

What are the main secreting cells of the adrenal medulla

Answer 4

Chromaffin cells

Question 5

When is adrenaline released

Answer 5

Response to activation of the sympathetic nervous system

Fibres of which are carried to the adrenal medulla by the thoracic splanchnic nerves

Question 6

What are adrenaline and noradrenaline produced from

Answer 6

Tyrosine

Question 7

Where is synthesised adrenaline stored

Answer 7

Vesicles before being released into the blood stream

Part of flight or fight response

Question 8

Describe the Zona Fasciculata

Answer 8

Middle zone of adrenal cortex

Made up of parenchymal cells

Function to secrete glucocorticoids - cortisol and corticosterone

Question 9

What is the role of cortisol

Answer 9

Hormone

Regulates carbohydrate metabolism - especially in flight or fight (time of stress)

Question 10

Approximately how much cortisol is secreted in an adult over a 24 hour time period

Answer 10

10mg

Question 11

Describe the production of cortisol

Answer 11

Cholesterol precursor

1. initiated by ACTH and angiotensin II - activate adenylyl cyclase and phospholipases C (respectively =)
2. cholesterol converted to pregnenolone by cytochrome P450
3. All mineralocorticoids, glucocorticoids and androgens can be synthesised from pregnenolone in a multi-step enzyme assisted pathway
4. In zona fasciculate enzyme 11b-hydroxylase catalyses final step of reaction that forms cortisol

Question 12

Describe the Zona Glomerulosa

Answer 12

Outermost of the adrenal cortex

Responsible for secreting mineralocorticoid hormones e.g. aldosterone

Question 13

Describe the Zona Reticularis

Answer 13

Innermost layer of the adrenal cortex

Responsible for the production and secretion of androgens

Question 14

What do most things produced by the adrenal cortex originate from

Answer 14

Cholesterol

Question 15

What is the role of the adrenal glands

Answer 15

Secrete steroid and catecholamine directly into the blood

Question 16

What does the cortex secrete

Answer 16

Two cholesterol derived hormones

• corticosteroids
• androgens

Question 17

What are the three functional groups of the cortex

Answer 17

Zona glomerulosa

Zona fasciculata

Zona reticularis

Question 18

What is the role of the zona glomerulosa

Answer 18

Produces and secretes mineralocorticoids e.g. aldosterone

Question 19

What is the role of zona fasciculata

Answer 19

Produces and secretes corticosteroids e.g. cortisol

Secretes a small amount of androgens

Question 20

What is the role of the zona reticularis

Answer 20

Produces and secretes androgens e.g. DHES

Secretes small amount of corticosteroids

Question 21

What is the role of medulla

Answer 21

Contains chromaffin cells

Secrete catecholamines e.g. adrenaline into the blood in response to stress

Question 22

What is the arterial supply to the adrenal glands

Answer 22

Superior, middle and inferior adrenal artery

Question 23

What is the innervation to the adrenal glands

Answer 23

Coeliac plexus
Greater splanchnic nerves

Sympathetic innervation to adrenal medulla via myelinated pre-synaptic fibres - T10-L1