endocrine system

Question 1

glands

Answer 1

widely separated secretory cells around capillaries

Question 2

where do ductless glands discharge into?

Answer 2

• discharge directly into blood vessels

Question 3

hormones

Answer 3

• chemical messengers carried to target

synthesised amino acids or steroids

Question 4

what is homeostasis controlled by?

Answer 4

controlled by autonomic NS or endocrine

system, through positive or negative feedback

Question 5

where does endocrine system give fine/subtle control too?

Answer 5

whole body, not just local area

Question 6

endocrine glands (13 glands)

Answer 6

 1 pituitary gland (+ hypothalamus)
 1 pineal body
 1 thymus
 1 thyroid gland
 4 parathyroid glands
 2 adrenal (suprarenal) glands
 The islets of Langerhans (Pancreas)
 2 ovaries or testes

Question 7

where do hormones bind ?

Answer 7

 Bind to receptor sites on target cells

 Water-soluble hormone receptor on the
cell wall
 Lipid-soluble hormone receptor inside cell
 Level is variable & self-regulated, gives
fine & subtle control
 Negative & positive feedback

Question 8

what do hormones control

Answer 8

Control chemical/metabolic actions in cell

Question 9

where is the Pituitary Gland & Hypothalamus located

Answer 9

Lies in hypophyseal fossa of sphenoid bone
Lies below hypothalamus and connected to it
by stalk called infundibulum

Question 10

what is Thyroid Hormone (TSH) stimulated by

Answer 10

Stimulated by TRH

hypothalamus

Question 11

what does thyroid gland secrete

Answer 11

thyroxin

Question 12

when is TSH at its highest

Answer 12

at night

Question 13

what type of feednach does TSH have

Answer 13

negative feedback

Question 14

what is Adrenocorticotrophic hormone (ACTH) stimulated by

Answer 14

stimulated by CRH from Hypothalamus. Increases cholesterol & steroids, esp.
Cortisol.

Question 15

when is ACTH at its highest and lowest

Answer 15

Highest 8am lowest midnight (circadian rhythm).

Neg feed back

Question 16

what does ACTH increase

Answer 16

increases cholesterol & steroids, esp. Cortisol.

Question 17

what does Prolactin stimulate

Answer 17

Prolactin Stimulates lactation – effect on breasts after parturition.
Stimulated by PRH hypothalamus. Inhibited by PIH. Relates to sleep.

Question 18

what is prolactin stimulated by

Answer 18

Stimulated by PRH hypothalamus.

Question 19

what is prolactin inhibited by

Answer 19

PIH

Question 20

Where are Gonadotrophins (sex hormones) secreted to stimulate ?

Answer 20

secreted to stimulate FSH & LH. This stimulates Oestrogen & Progesterone and
testosterone

Question 21

what are Posterior Pituitary made up of?

Answer 21

Made up of nervous tissue -Pituicytes

Question 22

what does oxytocin stimulate

Answer 22

Oxytocin stimulates 2 target tissues – uterine smooth

muscle & muscle of lactating breast. Positive feed back

Question 23

Antidiuretic hormone (ADH) or
Vasopressin. what does it reduce and how?

Answer 23

reduces urine output by increasing
water permeability of distal convoluted tubules in the
kidney.

Question 24

what are 2 thyroid glands

Answer 24

Thyroxin (T4) &

Triiodothyronine (T3)

Question 25

what does calcitonin act on?

Answer 25

``` on bone & kidneys to reduce blood calcium when raised. Opposite effect to parathyroid hormone (PTH) ```

Question 26

what is Parathyroid hormone – (PTH) secretion regulated by?

Answer 26

by calcium level (negative feedback)

Question 27

functions of Parathyroid hormone – (PTH)

Answer 27

Main function increase blood calcium when low Increases amount absorbed small intestine ……&/or Reabsorbed from renal tubules………….&/or Stimulates osteoclasts-destroys bone-Ca+ from bone

Question 28

what is Ca+ needed for?

Answer 28

Ca+ needed for muscle contraction, blood clotting, nerve impulse transmission

Question 29

Adrenal (Suprarenal) Glands

Answer 29

2 glands - 1 on each upper pole of kidney 4cm x 3cm Each in 2 parts with different functions Cortex – outer part Medulla – inner part

Question 30

what three types of hormones does Adrenal Cortex | Secrete

Answer 30

Glucocorticoids Mineralocorticoids Sex hormones

Question 31

Glucocorticoids

Answer 31

Regulates metabolism & response to stress. | Circadian rhythm.

Question 32

Functions of glucocorticoids | steroids) (4

Answer 32

``` Have anti-inflammatory action Suppress immune response  suppress tissue response to injury Delay wound healing ```

Question 33

Mineralocorticoids (aldosterone)

Answer 33

Maintenance balance water & electrolytes | Stimulates sodium reabsorption in renal tubules

Question 34

where does the Adrenal Medulla develop from?

Answer 34

 Develops from nervous tissue in embryo

Question 35

what does the Adrenal Medulla produce?

Answer 35

Produces adrenaline & noradrenaline

Question 36

Alpha cells secrete

Answer 36

glucagon

Question 37

Beta cells secrete

Answer 37

insulin

Question 38

Delta cells secrete

Answer 38

somatostatin (GHRIH)

Question 39

what is the normal blood glucose ?

Answer 39

2.5 – 5.3 mmol/lt

Question 40

what does the pineal gland excrete

Answer 40

Excretes melatonin

Question 41

Histamine

Answer 41

secreted by mast cells. Part of inflammatory response

Question 42

Serotonin

Answer 42

Contraction smooth muscle. Haemostasis

Question 43

Prostaglandins

Answer 43

Inflammatory response, pain, fever, BP, blood clotting

Question 44

Erythropoietin

Answer 44

Made in kidney. Blood formation

Question 45

Gastrointestinal hormones

Answer 45

Gastrin, secretin, cholecystokinin influence digestive | juices