Anatomical basis of homeostasis

Question 1

What are the classes of hormones

Answer 1

Amino acid derviatives (adrenaline)
Small peptides (ADH)
Proteins (insulin)
Steroids (cortisol)

Question 2

What are the characteristics of a peptide/hormone producing cell

Answer 2

Lots of RER, Golgi and secretory vesicles

Question 3

What are the characteristics of a steroid secreting cell

Answer 3

Lots of SER
Mitochondria
Lipid droplets

Question 4

How is the pituitary connected to the floor of the III ventricle

Answer 4

by the infundibulum just posterior to the optic chiasma

Question 5

Where is the pituitary gland

Answer 5

attached via the infundibulum just posterior to the optic chiasma

lies in a depression in the body of the sphenoid (pituitary fossa/sella turcica)

Question 6

What is another name for the pituitary fossa

Answer 6

sella turica

Question 7

What is the name of the layer covering the pituitary fossa

Answer 7

diaphragma sellae

Question 8

What are the two parts of the pituitary gland

Answer 8

adenohypophysis

neurohypophysis

Question 9

What are the subdivisions of the adenohypophysis

Answer 9

pars distalis, tuberalis, intermedia

Question 10

What are the subdivisions of the neurohypophysis

Answer 10

pars nervosa

Question 11

What is another name for the anterior pituitary

Answer 11

adenohypophysis

Question 12

What is another name for the posterior pituitary

Answer 12

neurohypophysis

Question 13

Describe the embryological development of the adenohypophysis

Answer 13

An upgrowth of the endo/ectoderm from the embryonic oral cavity (Rathke’s pouch)

Question 14

What is Rathke’s pouch

Answer 14

Upgrowth of ectoderm/endoderm of embryonic mouth cavity which forms adenohypophysis

Question 15

Describe the embryological development of the neurohypophysis

Answer 15

A downgrowth from the floor of diencephalon

Question 16

Describe the cellular strucure of the posterior pituitary

Answer 16

axons of neurons + population of glial like cell called pituicytes

Question 17

What is the name of the glial like cells in the pituitary gland

Answer 17

pituicytes

Question 18

Where are the cell bodies of the neurons whos axons travel through into the posterior pituitary

Answer 18

The cell bodies are in the supraoptic and paraventricular nuclei of hypothalamus

Question 19

What does ADH do

Answer 19

Increases water retention in the kidney

raises blood pressure by contracting smooth muscle cells

Question 20

Whar does oxytocin do

Answer 20

Contraction of smooth muscles cells- especially of uterus during childbirth + myoepithelial cells of mammary gland during lactation

Social and sexual bonding

Question 21

How long is the peptide chain in ADH/oxytocin

Answer 21

9 peptides

Question 22

What are herring bodies

Answer 22

Accumulations of hormone (ADH/oxytoxin) in axons

Question 23

What are the classifications of the cells in the pars distalis region of the anterior pituitary and how do they stain with H+E

Answer 23

Acidophils (pink/orange)
Basophils (blue)
Chromophobes (poorly)

Question 24

What do somatotrophs secrete

Answer 24

growth hormone

Question 25

What do mammotrophs secrete

Answer 25

prolactin

Question 26

What acidophils are in the pars distalis regoin of the anterior pituitary gland

Answer 26

somatotrophs and mammotrophs

Question 27

What basophils are in the pars distalis region of the adenohypophysis

Answer 27

thyrotrophs coriticotrophs gonadotrophs

Question 28

What do thyrotrophs secrete

Answer 28

TSH (thyroid stimulating hormone)

Question 29

What do corticotrophs secrete

Answer 29

adrenocorticotrophic hormon (ACTH)

Question 30

What do gonatotrophs secrete

Answer 30

Follicle stimulating hormone

Question 31

What type of cells makes up the pars tuberalis

Answer 31

thin layer of cuboidal cells, mostly gonadotrophs

Question 32

What type of cells make up the pars intermedia

Answer 32

melanocyte stimulating hormone (increases skin pigmentation)

Question 33

At which level does the isthmus lie

Answer 33

2nd-4th tracheal

Question 34

What is the isthmus of the thyroid

Answer 34

the bit that joins the two butterfly rings;

Question 35

Why is the isthmus sometimes joined to the hyoid bone by a fibrous cord

Answer 35

the fibrous cord is a remnant of the embryological thyroglossal duct

Question 36

Describe the embryological development of the thyroid

Answer 36

from a diverticulum in the floor of the pharynx

Question 37

What do the follicles of the thyroid gland secrete

Answer 37

thyroglobulin

Question 38

How is iodide metabolised in the thyroid

Answer 38

oxidised to iodine covalently attaches to the tyrosines of thyroglobulin in lumen of follicle

Question 39

What does TSH do on follicles with iodine

Answer 39

follicle cells endocytose the iodinated thyroglobulin + break it down in lysosomes release the iodinated tyrosine derivatives as tetraiodothyronine (thyroxine) or tri-iodithyronine

Question 40

What do thyroid C cells do

Answer 40

secrete calcitonin - inhibits Ca2+ mobilization from bone

Question 41

What does calcitonin do

Answer 41

inhibits Ca2+ mobilization

Question 42

What is the shape of the right adrenal gland

Answer 42

pyramidal

Question 43

What is the shape of the left adrenal gland

Answer 43

cresent

Question 44

What are the layers and development of the adrenal glands

Answer 44

Cortex - derived from coelomic epithelium Medulla - derived from adjacent sympathetic ganglion

Question 45

What are the layers of the adrenal cortex

Answer 45

zona glomerulosa, fasciulata, reticularis

Question 46

What is the purpose of the zona glomerulosa

Answer 46

secretes mineralocorticoids (aldosterone)

Question 47

Where is aldosterone secreted from

Answer 47

zona glomerulosa in cortex of adrenal gland

Question 48

What is the function of zona fasciculata

Answer 48

glucocorticoids (cortisol)

Question 49

Where is cortisol released from

Answer 49

zona fasciculata of cortex of adrenal gland

Question 50

How is the medulla of the adrenal glands controlled

Answer 50

via preganglionic sympathetic input from greater and lesser splanchnic nerves via coeliac ganglion

Question 51

What does the medulla of the adrenal gland do

Answer 51

secretes catecholamines into blood

Question 52

What are the functions of the different cell types in the islets of Langerhands

Answer 52

A - secrete glucagon B - secrete insulin D - somatostatin F - pancreatic polypeptide