Anatomy of the endocrine system

Question 1

what are the names of the main endocrine organs in the body?

Answer 1

pineal gland

thymus

parathyroidglands

thyroid gland

adrenal glands

pancreas

placenta (during pregnancy)

ovaries

testes

Question 2

the pituitary gland sits in a hollow in the skull

what is the hollow called and in what bone of the skull is it situated?

Answer 2

pituitary fossa/sella turcica

sphenoid bone

Question 3

how is the optic chiasm related to the pituitary gland?

Answer 3

the optic chiasm is directly above the pituitary gland

Question 4

clinical: enlargement of the pituitayr gland in disease often impinges on the crossing fibres of the optic chiasm

which fibres form the optic nerve, nasal or temporal, cross over to the opposite side at the chiasm?

what therefore would the resultant visual defect be due to pituitary gland enlargement?

Answer 4

nasal

loss of temporal vision - bitemporal hemianopia

Question 5

Question 6

a

Answer 6

mamillary body

Question 7

b

Answer 7

pituitary stalk

Question 8

c

Answer 8

posterior pituitary

Question 9

d

Answer 9

hypothalamus

Question 10

e

Answer 10

optic chiasm

Question 11

f

Answer 11

pars intermedia

Question 12

g

Answer 12

anterior pituitary

Question 13

what is the larger of the two lobes of the pituitary gland?

Answer 13

anterior pituitary

Question 14

which of the two lobes of the pituitary gland is glandular and manufactures numerous hormones?

Answer 14

anterior

Question 15

what is the function of the posteiror pituitary?

Answer 15

stores and secretes two hormones made in the hypothalamus

Question 16

does the anterior or posterior pituitary stain darker?

Answer 16

anterior - darker

posterior - pale

Question 17

what cells are seen in the anterior pituitary and what colour do they stain?

Answer 17

acidophilic (stain pink)

basophilic (stain light purple)

chromophobic (dont take up much stain and therefore appear pale)

Question 18

whata re the different classes of acidohpil?

Answer 18

somatotrophs

mammotrophs

Question 19

what is the secretory product and target organ of somatotrophs?

Answer 19

GH

all tissues

Question 20

what is the secretory product and target organ of mammotrophs?

Answer 20

prolactin

mammary gland

Question 21

what are the different classes of basophil?

Answer 21

corticotrophs

tyhrotrophs

gonado-trophs

Question 22

what is the secretory product and target organ of corticotrophs?

Answer 22

ACTH and MSH

adrenal gland and skin

Question 23

what is the secretory product and target organ of thyrotrophs?

Answer 23

TSH

thyroid gland

Question 24

what is the secretory product and target organ of gonado-trophs?

Answer 24

FSH and LH

Ovaries/Testes

Question 25

what are the main secretory cells of the posterior pituitary?

Answer 25

neurosecretory ccells magnocellular neurones

Question 26

what hormones do the cells of the posterior pituitary secrete?

Answer 26

ADH oxytocin

Question 27

what is the blood supply of the hypothalamus?

Answer 27

branches of the ICA - the superior and inferior hypophysial arteries the superior hyophysial artery enters into the substance of the hypothalamus before breaking up into capillaries (the hypophysial portal system). these capillaries then supply the anterior pituitary gland the inferior hypophysial artery supplies the posterior pituitary gland

Question 28

how does the hypothlamus communicate with the anterior pituitary?

Answer 28

special portal blood system - hypothalamus-hypophyseal

Question 29

how does the hypothalamus communicate with the posteiror pituitary?

Answer 29

neurons - magnocellular

Question 30

venous drainage is through what?

Answer 30

hypophysial veins into the cavernous sinus

Question 31

where is the thyroid gland located?

Answer 31

in the neck anterior to the trachea and just inferior to the larynx located between the level of C5 and T1 and between the thyroid cartilage and the 6th tracheal ring the isthmus lies opposite the 2nd and 4th tracheal rings

Question 32

what are the 3 strap muscles that overlie the thyroid gland?

Answer 32

sternohyoid omohyoid (anterior belly) sternothyroid

Question 33

name the two nerves that supply the muscles of the vocal cords and describe their location in relation to the thyroid gland

Answer 33

1. recurrent laryngeal nerve - tuns between trachea and oesophagus 2. external laryngeal nerve (branch of the superior laryngeal nerve) - lies close to superior thyroid artery

Question 34

form which major artery in the neck does the superior thyroid artery arise?

Answer 34

ECA

Question 35

from which artery doe sthe inferior tyhroid artery arise?

Answer 35

subclavian artery

Question 36

into which vein does the superior thyroid vein drain?

Answer 36

IJV

Question 37

into which vein does the middle thyroid vein drain?

Answer 37

IJV

Question 38

into which vein does the inferior thyroid vein drain?

Answer 38

brachiocephalic vein (left)

Question 39

most lymph vessels form the thyroid gland drain into the ______ \_\_\_\_\_\_\_\_ group of lymph nodes

Answer 39

deep cervical

Question 40

the hormones of the thyroid gland are stored in \_\_\_\_\_\_\_, surrounded by _______ cells. these make up a \_\_\_\_\_\_. within the cavity of the follicle, the hormone is bound to a __________ and is called as \_\_\_\_\_\_. during secretion the hormones is re-absorbed from the cavity, and then released into surrounding interstitial spaces

Answer 40

cavities secretory follicle glycoprotein colloid

Question 41

what type of cell do you see lining the follicle?

Answer 41

follicular cells simple cuboidal epithelial

Question 42

what colour does the colloid stain (in a H&E stained slide)?

Answer 42

pink

Question 43

what do clear/parafollicular/C cells secrete?

Answer 43

calcitonin Calcitonin is involved in helping to regulate levels of calcium and phosphate in the blood, opposing the action of parathyroid hormone Secretion of this hormone is controlled directly by the blood's calcium levels. When the levels start to increase, the body responds with increased calcitonin levels

Question 44

what hormone does the thyroid gland secrete?

Answer 44

T3 - Triiodothyronine T4 - thyroxine

Question 45

the parathyroid glands lie on the _____ half of the ______ surface of each thyroid lobe, external to the thyroid fibrous capsule most people have 4 they are seperated from the thyroid gland by a think ______ capsule

Answer 45

lateral posterior fibrous

Question 46

where are the superior and inferior parathyroids situated?

Answer 46

the superior parathyroids are situated at the level of the inferior border of the cricoid cartilage the inferior parathyroids are usually near the inferior poles of the thyroid, though their position is variable

Question 47

what is arterial and venous drainage of the arathyroid glands?

Answer 47

arterial supply to both superior and inferior parathyroids is predominantly form the inferior thyroid arteries venous drainage is via the veins draining the thyroids to the internal jugular veins

Question 48

what types of cells are seen in the parathyroid?

Answer 48

cheif cells oxyphil cells cheif cells are mor enumerous and have a darker staining cytoplasm

Question 49

what hormone is secreted by the parathyroid gland and what is the action of this hormone?

Answer 49

parathyroid hormone: decreases phosphate increases plasma calcium

Question 50

what cells does parathyroid hormone act upon and what is their subsequent action?

Answer 50

stimulates osteoclasts to increase release of Ca2+ inhibit osteoblasts to reduce Ca2+ dpeosition in bone increase Ca2+ reabsorption from kidney tubules increase renal excretion of phosphate stimulates kidney to synthesise calcitriol from vit D which promotes calcium absorption at the gut and kidney

Question 51

are the adrenal glands retroperitoneal or intraperitoneal?

Answer 51

retroperitoneal

Question 52

what are the two parts of the suprarenal glands and what do they develop from?

Answer 52

outer cortex - mesodermal epithelium inner medulla - neuroectoderm

Question 53

what is the blood supply of the adrenal glands?

Answer 53

suprarenal arteries that arise from the inferior phrenic arteries, the aorta and renal arteries

Question 54

where does the superior, middle and inferior adrenal arteries come form?

Answer 54

superior - inferior phrenic middle - aorta inferior - renal arteries

Question 55

there is only one suprarenal vein into which vein does the suprarenal vein drain?

Answer 55

on right side - IVC on left side - left renal or left inferior phrenic vein

Question 56

what are the layers of the cortex?

Answer 56

zone glomerulosa (thin) zona fasiculata (thick) zone reticularis - immediatley adjacent to the medulla)

Question 57

what does the medulla contain and secrete?

Answer 57

the medulla has large collections of large ovoid chromaffin cells which secrete adrenalin and noradrenalin

Question 58

what are the 3 main hormone types secreted form each of the three zones?

Answer 58

zona glomerulosa - Mineralocorticoids - aldosterone zona fasiculata - Glucocorticoids - cortisol zona reticularis - androgens (medulla - epinepharine and norepinepharine)

Question 59

is the pancreas retroperitoneal or intraperitoneal?

Answer 59

retroperitoneal

Question 60

a

Answer 60

hepatic artery

Question 61

b

Answer 61

splenich artery

Question 62

c

Answer 62

inferior mesenteric artery

Question 63

d

Answer 63

superior mesenteric artery

Question 64

differentiate the exocrine part of the pancreas (pacnreatic acini) form the endocrine part (Islets of Langerhans) what type of cell types are found within the Islets of Langerhans and what do they secrete?

Answer 64

a - glucagon b - insulin delta - somatostatin