Endocrinology

Question 1

Define homeostasis?

Answer 1

O

Question 2

Which time of the day does cortisol peak?

Answer 2

Morming

Question 3

Where is our biological clock located? What hormone is responsible for setting the biological clock?

Answer 3

Suprachiasmatic Nucleus (SN)

Melatonin from pineal gland

Question 4

Which is the most common form of feedback in physiological systems?

Negative or positive?

Answer 4

Negative

Question 5

Give examples of positive feedback?

Answer 5

• blood clotting

- ovulation

Question 6

Differentiate btw Osmolarity and Osmolality

Answer 6

OsmolaRity= # of osmoles per LITRE of solution (VOLUME)

OsmolaLity= # of osmoles per KG of solution
MASS

Question 7

When is measuring serum osmolality useful?

Answer 7

When investigating Hyponatraemia (low Na+ in blood)

Reference range: 275-295 mOsmol/Kg

Question 8

What monitors the osmostic pressure of blood plasma?

Answer 8

Osmosrecepters in the hypothalamus

Question 9

Adrenal medulla hormones_______soluble •

Thyroid hormones _______soluble

Answer 9

Water

Lipid

Question 10

Name some steroid hormones derived from cholestrol

Answer 10

Cortisol
Aldosterone
Testosterone

Question 11

Hormones circulate in blood at very LOW concentrations

Answer 11

Ok

Question 12

Steroid hormones are synthesised from ________

Answer 12

Cholestrol

Question 13

What type of recepter does watersoluble hormones bind on? Lipid soluble

Answer 13

Cell surface recepters

GPCR
TYROSINE

Intacellular recpter

Recpeter complex is acting on DNA on gene expression,

***thats why the response for steroid hormones is LONGER, bc there synthesis of NEW proteins occuring

Question 14

Where is the appetite control centre located?

Answer 14

Hypothalamus, Arcuate nucleus

Controlls apetite