Endocrine System

Question 1

What type of glands is the endocrine system made up of?

Answer 1

Endocrine glands that are ductless

Question 2

What do the endocrine glands do?

Answer 2

Release product into the bloodstream for transportation to target tissues

Question 3

What chemical signals are produced by the endocrine gland?

Answer 3

Hormones

Question 4

What makes something a target for hormones?

Answer 4

Cells or organ that have receptors that bind to the hormone

Question 5

What are the names of the 2 types of target receptors for hormones?

Answer 5

Surface and Nuclear Receptors

Question 6

Where is the pancreas close to?

Answer 6

1st part of the small bowel and anatomically in contact with stomach and other areas

Question 7

What hormones do the pancreas secrete?

Answer 7

Insulin, glucagon, gastrin, somatostatin and vasoactive intestinal peptide (vip)

Question 8

What does gastrin do?

Answer 8

Stimulates gastric acid production and tells you when you’re hungry

Question 9

What does somatostatin do?

Answer 9

Inhibits release of other hormones like growth, thyroid, insulin and glucagon

Question 10

What does vasoactive intestinal peptide do?

Answer 10

Regulates gut water and electrolyte secretion

Question 11

What do the anterior and posterior pituitary both do?

Answer 11

Communicate with the hypothalamus and are the orchestra of the endocrine system. Secreting hormones that are affectors of other glands

Question 12

What hormones do the anterior pituitary secrete?

Answer 12

Prolactin - breasts
LH & FSH - Ovarian and testosterone levels
ACTH - Adrenal cortex drives cortical hormones
TSH - Thyroid gland for thyroid hormones

Question 13

What hormones do the posterior pituitary secrete?

Answer 13

Oxytocin - breast and uterus during childbirth
Vasopressin (ADH) - maintain salt and water balance in the kidneys

Question 14

What does pituitary dysfunction lead to?

Answer 14

Hormone excess, hormone deficiency and tumour mass effects (causing bitemporal hemianopia)

Question 15

Where is the thyroid gland located?

Answer 15

In the neck, just below the thyroid cartilage and is butterfly shaped.

Question 16

Where it the laryngeal nerve?

Answer 16

Runs posterior to the thyroid

Question 17

Where are the internal jugular vein and common carotid artery in relation to the thyroid?

Answer 17

Postero-lateral to the thyroid

Question 18

What two hormones do the thyroid secrete?

Answer 18

T4 (thyroxine) and T3 (tri-idothyronine)

Question 19

What is the role of thyroid hormones?

Answer 19

To regulate basal metabolic rate (i.e. metabolism)

Question 20

Is there more T4 or T3?

Answer 20

T4! It’s a 14:1 ratio

Question 21

What’s the difference between T3 and T4?

Answer 21

T3 is the biologically active hormone whereas T4 is the circulating store that’s converted to T3 outside of the thyroid at the target tissues

Question 22

What happens if there isn’t enough T3 or T4?

Answer 22

If there isn’t enough T3 or T4 this is fedback to the pituitary and the hypothalamus that release hormones. Pituitary releases Thyroid Stimulating Hormone (TSH) and the Hypothalamus releases Thyrotropin Releasing Hormone (TRH) that act on the thyroid to increase hormone T3 or T4 secretion)

Question 23

What are the symptoms of an overactive thyroid?

Answer 23

Weight loss, heat intolerance, tachycardia, diarrhoea, tremor and hyperactivity

Question 24

What are the symptoms of an underactive thyroid?

Answer 24

Weight gain, cold intolerance, bradycardia, constipation and lethargy

Question 25

How does Grave’s Disease occur?

Answer 25

The result of an overactive thyroid.

Question 26

What happens in Grave’s Disease?

Answer 26

Where Thyroid Stimulating Hormone (TSH) receptor auto-antibodies attack the thyroid causing it to produce too much T3 and T4. It also attacks the periorbital muscles to cause swelling which damages the cornea.

Question 27

How many parathyroids do we have?

Answer 27

Usually 4, size of a grain of rice

Question 28

What’s the role of the parathyroid?

Answer 28

To regulate serum calcium, any drop in it is sensed by the parathyroid gland that releases parathyroid hormones that act on the kidney for the reabsorption of Ca2+ in the gut and bones.

Question 29

What are the symptoms of an overactive parathyroid (hypercalcaemia)?

Answer 29

Thirst, polyuria, fatigue, constipation, renal stones, osteoporosis and cardiac dysrhythmia

Question 30

What’s a symptom of an underactive parathyroid (hypocalcaemia)?

Answer 30

Tetany (pins and needles), muscle spasm, confusion and cardiac dysrhythmia

Question 31

The adrenal is separated into the medulla and cortex, what are the 3 zones of the cortex and what are they for?

Answer 31

Zona Glomerulosa (androgens)
Zona Fasciculata (cortisol)
Zona Reticularis (aldosterone)

Question 32

Steroid hormone synthesis is complicated. They’re originally generated from cholesterol, what are the 4 end paths?

Answer 32

Cortisol
Corticosterone
Aldosterone
Androstenedione

Question 33

What is cortisol for?

Answer 33

Stress response (slow releasing, in fight or flight it would be adrenaline), releases glucose by Glycolysis and maintains blood pressure

Question 34

What’s an adrenal cortex disease?

Answer 34

Addison’s Disease - Adrrnal insufficiency (cortisol & aldosterone)

Question 35

What does the adrenal medulla do?

Answer 35

Synthesises catecholamines being adrenaline and noradrenaline (stress hormones)

Question 36

What are adrenal hormones stimulated by?

Answer 36

CNS and SNS

Question 37

What type of pathway is the adrenal pathway?

Answer 37

It’s a neuronal afferent pathway with an endocrine efferent pathway