HYPOPHYSIS (PITUITARY GLAND) HISTOLOGY AND DEVELOPMENT

Question 1

Target cell activation of a hormone depends on

Answer 1

Activation depends on 3 factors:
• Blood levels of the hormone
• Relative number of receptors on the target cell
• Affinity of those receptors for the hormone

Question 2

Types of hormones

Answer 2

Peptide hormones
Lipid derivatives
Amino acid derivatives
thyroid hormones and epinephrine norepinephrine

Question 3

How Hormones Work

Answer 3

1. Activate Second Messengers (Involves regulatory G proteins)
   (This is how amino acid-derived, peptide, and fatty acid-derived hormones work)
2. Activate Genes
   (This is how steroid and thyroid hormones work)

Question 4

Parts of pituitary

Answer 4

Anterior pituitary
Pars distal is
Pars tuberalis
Parts intermedia

Posterior pituitary
Pars nervous
Infindubular stalk

Question 5

The pituitary gland is entirely

Answer 5

Ectodermal

Question 6

Anterior lobe of pituitary gland is derived from

Answer 6

Ratkhe’s pouch

Question 7

Posterior lobe of pituitary is derived from

Answer 7

neuroectoderm of
the floor of the third ventricle (the diencephalon) of the
developing brain.

Question 8

….. contains the neurosecretory axons forming the
23hypothalamohypophysial tracts.

Answer 8

Infindibulum

Question 9

Superior hypophyseal arteries

Answer 9

supply the pars tuberalis,
median eminence and infundibulum. These vessels arise from
the internal carotid arteries and posterior communicating artery
of the circle of Willis.

Question 10

Inferior hypophyseal arteries

Answer 10

primarily supply the pars
nervosa. These vessels arise solely from the internal carotid
arteries.

Question 11

Percentages

Answer 11

GH 50
TSH 5
PRL 20
ACTH 20
FFSH LH 10

Question 12

Cells of pars distalis

Answer 12

-Basophils
1 Corticotropes (ACTH cells)
-Acidophils
2 Gonadotropes(FSH and LH cells)
3 Thyrotropes ( TSH cells)
1 somatotrops (GH cells)
2 Lctotrops (PRL mammatrops)
-Chromophobes
Follicular stellate cells

Question 13

3 hormones regulate the release of PRL

Answer 13

1 Dopamine ——— inhibitory
2TRH
3VIP ————- stimulitaey

Question 15

The parenchymal cells of pars intermedia surrounds
colloid-filled follicles

Answer 15

(Rathke’s cysts

Question 16

The pars intermedia contains

Answer 16

basophils and
chromophobes
Basophils synthesize proopiomelanocortin. Alpha and beta MSH

Question 18

NEUROSECRETORY
VESİCLES

Answer 18

Herring bodies

Question 19

Cells of pars nervosa

Answer 19

Pituicytes