Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Histology > Endocrine > Flashcards

Endocrine Flashcards

(131 cards)

Start Studying
1
Q

2 parts of pituitary gland

A

Anterior and posterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Origin of posterior pituitary

A

Neuronal origin
Down-growth of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What attaches the posterior pituitary to the brain

A

Pituitary stalk to the median eminence of the midbrain in the floor of the third ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is the posterior pituitary attached to the brain

A

Median eminence of midbrain in the floor of the third ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which hormones does the posterior pituitary secrete

A

Vasopressin (ADH)
Oxytocin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the posterior pituitary contain

A

Nerve endings of axons whose cell bodies lie in the supraoptic and para-ventricular nuclei of hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Origin of anterior pituitary

A

Epithelial in origin
Derived from roof of primitive gut tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Adherence of anterior pituitary

A

Adheres to anterior border of posterior pituitary
Surrounds the pituitary stalk (pars tuberails)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What regulates the release of trophic hormones from the anterior pituitary gland

A

Releasing or inhibiting factors produced by neurons of the hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does the hypothalamus communicate with the anterior pituitary gland

A

Pituitary portal system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

3 sub groups of cells in the anterior pituitary

A

Alpha cells/acidophils
Beta cells/basophils
Chromophobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which cells stain weakly with either type of dye

A

Chromophobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which cells fail to stain

A

Immature cells without granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which cells stain heavily with acid dyes

A

Alpha cells/ acidophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which cells stain heavily with basic dyes

A

Beta cells/ basophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

5 main classes of cell in anterior pituitary

A

Somatotrophs
Lactotrophs
Corticotrophs
Thyrotrophs
Gonadotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do Somatotrophs secrete

A

Growth hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do Lactotrophs secrete

A

Prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do Corticotrophs secrete

A

Adrenocorticotropin hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do Thyrotrophs secrete

A

Thyroid stimulating hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do Gonadotrophs secrete

A

Follicle stimulating hormone
Luteinising hormome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Staining the posterior pituitary

A

Stains palely with H&E in routine wax embedded tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Herring bodies

A

Swollen nerve terminals containing dark staining neuro-secretory granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Neurophysin

A

Carrier protein in posterior pituitary that binds to ADH or oxytocin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Adenohypophysis
Anterior pituitary - epithelial origin
26
Neurohypophysis
Posterior pituitary- neuronal origin
27
What colour do neuro-secretory granules (I.e. posterior pituitary) stain
Brown
28
Pars tuberalis
An upward extension of the anterior pituitary that surrounds the pituitary stalk to form the tuberal lobe Contains mostly gonadotrophic cells
29
Which cell type is mostly found in the pars tuberalis
Gonadotrophic
30
Intermediate lobe
Lies between the anterior and posterior pituitary Contains cyst-like aggregations of colloidal material
31
Pineal gland location
Backward projection from the 3rd ventricle below the corpus callosum Covered by meninges
32
Function of pineal gland
Secretes melatonin
33
Function of melatonin
Regulator of diurnal rhythm
34
Innervation of pineal gland
Autonomic
35
Structure of pineal gland
Irregular clumps of neuron-like pinealocytes linked by glial cells Calcium accumulates as particles in its capsule
36
Why does the pineal gland appear radio opaque and visible on x-rays
Calcium accumulates as particles in its capsule
37
Location of thyroid gland
Arises from floor of the mouth (stomatodeum) Descends during development to lie in neck between the level of the thyroid cartilage superiorly and the 4th tracheal ring inferiorly
38
Structure of thyroid gland
2 lobes joined in the mid-line by an isthmus
39
Function of thyroid gland
Synthesises, stores and secretes thyroxine and calcitonin
40
Where are the parathyroid glands located
Embedded in posterior border of each lobe of thyroid gland
41
What links the thyroid gland to the Foramen caecum of the tongue
Midline thyroglossal ligament
42
Thyroid follicles
Form a single layered cuboidal epithelium surrounded by a basement membrane Centre of each follicle is filled with amorphous colloid rich in thyroglobulin Height of cells depends on metabolic activity
43
Thyroglobulin
Inert stored form of thyroxine hormone
44
First thyroid follicle phase- synthetic phase
Synthesis of thyroglobulin and store it within the follicle (upper panel)
45
2nd phase of thyroid follicle
Dormant period
46
3rd phase of thyroid follicle- resorbtive phase
Cells re-absorb and breakdown the colloid releasing the active hormone, mainly T4 (tetraiodothyronine), into the bloodstream (lower panel)
47
Characteristics of thyroid follicles in active phase
Cells enlarge and appear columnar in shape
48
Characteristics of thyroid follicles in dormant phase
Loose some organelles More stored colloid Low cuboidal profile
49
Where are C cells located
Thyroid gland In clumps between the follicles (parafollicular cells)- some occur singly, trapped between the basement membrane and epithelial cells of the follicle
50
Function of C cells
Produce calcitonin
51
Composition of parathyroid glands
A mixture of fat cells (adipocytes) and secretory cells
52
Secretory cells of parathyroid gland structure
Arranged in clusters or short cords
53
Main type of secretory cells in parathyroid gland
Chief cells
54
Structure of chief cells
10um in diameter Palely stained Contain large numbers of very small granules
55
Types of secretory cells in parathyroid gland
Chief cells Oxyphil cells
56
Oxyphil cells
Larger pink-staining Fewer numbers than chief cells Role is uncertain
57
Pancreatic islets of Langerhans
Small spherical masses of endocrine cells embedded throughout the exocrine pancreas Constitute about 5% of the mass of the gland Most numerous at the tail
58
Where are pancreatic islets of Langerhans most numerous in the pancreas
Tail
59
Number of cell types in islets of Langerhans
5
60
5 secretory cell types in islets of Langerhans
Insulin secreting beta cells Glucagon secreting alpha cells Somatostatin secreting delta cells Pancreatic polypeptide secreting cells Ghrelin secreting cells
61
What percentage of the islets of Langerhans is made up of insulin secreting beta cells
70%
62
What percentage of the islets of Langerhans is made up of glucagon secreting alpha cells
20%
63
What percentage of the islets of Langerhans is made up of somatostatin secreting delta cells
8%
64
What percentage of the islets of Langerhans is made up of pancreatic polypeptide secreting cells
2%
65
What percentage of the islets of Langerhans is made up of ghrelin secreting cells
<1%
66
What is required to differentiate between types of secretory cells in the islets of Langerhans
Immunohistochemical staining
67
What colour do the islets of Langerhans stain
Pale
68
Which cells are mostly distributed around the periphery of the islets of Langerhans
Beta cells
69
Distribution of beta cells
Mainly around the periphery of the islets and form anastomosing cords that penetrate to the centre of the
70
Location of adrenal glands
In the abdomen superior to the kidney Enclosed within renal fascia
71
Structure of adrenal glands
Outer cortex Inner medulla
72
Centripetal blood supply to adrenal gland
Arterioles from the capsular arteries supply the cortical sinusoids and provide direct links to the medulla (medullary arterioles) Both systems drain into the same central vein that carries the mixed cortical and medullary hormones to the renal vein (left) or IVC (right)
73
3 zones of adrenal cortex
Outer glomerular zone Intermediate fascicular zone Inner reticular zone
74
Outer glomerular zone of adrenal gland
Narrow Rounded clumps of cell Produces aldosterone and other mineralocorticoids
75
Intermediate fascicular zone of adrenal gland
Thick Long parallel cords of cells Produce cortisol and other glucocorticoids
76
Inner reticular zone of adrenal gland
Anastomosing cords of cells Produce testosterone and other androgenic hormones
77
Where are the hormones produced by the adrenal cortex stored
Sinusoids that run between the cords of cells
78
Why are the secretory cells of the adrenal cortex pale staining
Accumulate droplets of fat and cholesterol from the hormones that are synthesised
79
Structure of adrenal medulla
Irregular clumps of cells interspersed by blood vessels
80
2 types of secretory cells in adrenal medulla
1. Synthesise and secrete adrenaline 2. Secrete noradrenaline
81
Are the hormones in the adrenal cortex stored
No- discharge into sinusoids that run between the cords of cells as soon as produced
82
Are the hormones synthesised in the adrenal medulla stored
Yes- in small neurosecretory granules within the cytoplasm of cells until required
83
What influences cells of the adrenal medulla
Steroid hormones produced by the adrenal cortex in the blood that bathes the cells Autonomic (mainly sympathetic) innervation
84
Central vein in adrenal medulla
Large vein Thickened by bundles of smooth muscle fibres that run parallel to the vein, foreshortening it and helping to keep it open
85
Other hormone secreting tissues
Ovary Testis Placenta
86
Locations of isolated clumps of neuro-endocrine cells
Epithelium of the gut Respiratory tract Paraganglia Carotid bodies
87
What do acidophils secrete
Growth hormone Prolactin
88
What do basophils secrete
Thyrotrophs Corticotrophs Gonadotrophs
89
From which brain nuclei do the neurons that give rise to herring bodies originate
Supraoptic and paraventricular nuclei in the walls of the third ventricle and receive input from the hypothalamus
90
What stimulates calcitonin secretion
High blood calcium
91
Action of calcitonin
Lowers serum calcium by promoting the uptake of calcium in the blood particularly into bones and muscles Inhibits absorption of calcium from the gut and reabsorption of calcium in the kidney
92
What hormone has an antagonist action to calcitonin
Parathormone
93
Action of oxytocin on the uterus
Contraction of muscles of uterus Dilation of birth canal
94
Action of oxytocin on breasts
Contraction of smooth muscle in nipple causing it to become erect Contraction of myoepithelial cells of secretory alveoli aiding expression of milk
95
What hormone do chief cells produce
Parathormone
96
Action of parathormone
Mobilisation of calcium mainly from the bones
97
Which hormone secreting glands are derived directly from the primitive gut tube
Anterior pituitary Thyroid Parathyroid glands Endocrine pancreas
98
Where are Catecholamines produced
Chromaffin cells of adrenal medulla Post ganglionic fibre of sympathetic nervous system
99
Cells of adrenal medulla are derived from 2 distinct embryonic primordia - what are they
Modified postganglionic axons of sympathetic nervous system Derived from neural crest Synthesise melanin and small granules can be seen in the cytoplasm
100
All endocrine organs are composed of glandular epithelium apart from….
Posterior pituitary
101
What percentage of cells in the anterior pituitary are somatotrophs
50%
102
What percentage of cells in the anterior pituitary are Lactotrophs
25%
103
What percentage of cells in the anterior pituitary are Corticotrophs
15-20%
104
What percentage of cells in the anterior pituitary are Gonadotrophs
10%
105
What percentage of cells in the anterior pituitary are Thyrotrophs
1%
106
Where are somatotrophs predominantly found in the anterior pituitary
Lateral wings Present throughout
107
Lactotrophs structure
Polygonal cells Cytoplasmic processes wrap around other cells Variable prolactin staining
108
Thyrotrophs structure
Angular Chromophobes Elongated cytoplasmic processes Variable TSH staining
109
Gonadotrophs structure
Scattered round/oval cells Stain with either: Alpha subunits Beta LH beta FSH
110
Corticotrophs structure
Round basophilic cells Median of gland Large cytoplasmic vacuoles- enigmatic bodies
111
What supports pituicytes in the anterior pituitary
Sustentacular cells Surrounds the normal follicles Stains with S100
112
Pituitary adenoma
Benign tumour of pituitary
113
Structure of pinealocytes
Eosinophilic cytoplasm Central rounded nuclei Arranged in rosettes
114
Parathyroid chief cell structure
Polygonal cells Scant cytoplasm
115
How to determine between parathyroid and thyroid tissue
Parathyroid= no calcium oxalate crystals
116
Parathyroid Oxyphil cell structure
Large polygonal cells Increase with age Abundant eosinophilic cytoplasm Finely granular- rich in mitochondria
117
Number of islets of Langerhans in pancreas
Approximately 1 million
118
What secretes adrenaline and noradrenaline
Chromaffin cells
119
Which statement concerning endocrine organs is true?
All have a rich vascular supply
120
Which are the least common cells in the anterior pituitary?
Thyrotrophs
121
Which are the most common cells in the anterior pituitary?
Somatotrophs
122
Parathyroid chief cells…
Have scanty cytoplasm
123
Which gland contains fat cells
Parathyroid glands
124
The adrenal zona fasciculata principally secretes
Cortisol
125
Which hormones are produced by the islets of Langerhans
Insulin Glucagon Somatostatin Pancreatic polypeptide Ghrelin
126
Which endocrine organ receives its blood supply through a portal circulation?
Anterior pituitary
127
What hormones are produced by arachidonic acid
Prostaglandins
128
What is produced from glutamic acid
Histamine
129
What is produced from tryptophan
Melatonin
130
What is produced from cholesterol
Adrenal cortical hormones (steroid)
131
What is produced from tyrosine
Thyroxine Catecholamines Peptide

Histology (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions