Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Endo Repro Midterm > Histology of Endocrine Organs > Flashcards

Histology of Endocrine Organs Flashcards

1
Q

Major Glands and Organs associated with Endocrine System

LO1

A
  • hypothalamus
  • pineal
  • pituitary
  • thyroid
  • parathyroid glands
  • adrenal glands
  • pancreas
  • Gonads
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is the blood supply to endocrine organs so robust?

LO1

A

hormones are distributed throughout the body by cardiovascular system
- communication is much slower but effects on target cell.organs are of longer duration

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

Location of hypothalamus

LO2

A

part of the brain located below the thalamus, behind the optic chiasma and surrounding the 3rd ventricle

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

Hypothalamus
- anatomical relationship with pituitary gland

LO2

A

above the pituitary gland

primary site where CNS controls endocrine functions via pituitary glands

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

Target Organs and cells the are directly targeted by the hypothalamus

LO2

A
  1. anterior pituitary glands ( releasing and inhibiting factors)
  2. Kidney and uterus (releasing antidiuretic hormone and oxytocin, in posterior pituitary)
  3. Adrenal medulla (sympathetic innervation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Major lobes and parititions of the pituitary gland

  • location
  • nickname

LO3

A

aka Hypophysis

location: inferior to hypothalamus
- small, slightly oval gland house within hypophyseal (sella turcica) of sphenoid bone
- connected to hypothalamus by a thin stalk of tissue (infundibulum)
- partitioned structurally and functionally into anterior (adenohypophysis) and posterior (neurohypophysis) portions

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

Steroid Hormones

A

types of lipids derived from cholesterol

exm. estrogen , testosterone, cortisol

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

What controls hormonal release? (3)

A
  1. humoral stimuli
  2. neuronal stimuli
  3. hormonal stimuli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Humoral stimuli

A

release controlled by monitoring levels of ions and nutrients in blood and body fluids

exm. release of parathyorid hormone stimulated by low serum calcium levels

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

Neuronal Stimuli

A

release stimulated by nerve signals

exm. release of epinephrine from adrenal glands in response to a signal form sympathetic nerve fibers

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

Hormonal Stimuli

A

release caused by a hormone secreted into bloodstream by another endocrine organ or cell

exm. release of thyroid hormone stimulated by release of hormone, TSH from pituitary

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

Endocrine Gland Organization

A

Epitheloid cells (lacking free surface) arranged as cords/follicles and some as isolated individual cells

derived from epitheia

well- vascularized- vesels often have fenestrated endothelium

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

Indirect Targets of hypothalamus hormones

A
  1. Tropic (releasing/inhibitory) hormones
    - hypothalamus releases hormones (tropic) that stimulate or inhibit release of other hormones from anterior pituitary
  2. indirectly influences by stimulating secretion of hormones by anterior pituitary glands
    - thyroid glands
    - adrenal cortex
    - mammary gland
    - gonads- testes or ovaries
    - bone and other organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Microscope features of both anterior and posterior pituitary glands

LO4

A
  • Pars distalis
  • Pars Nervousa
  • pars tuberalis
  • pars intermedia
  • cyst intermedia - remnants of lumen of Rathke’s pouch
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Major cell types found within the anterior and posterior pituitary gland
- short description

LO4

A
  1. somatotropic cells
    - secrete growth hormone (GH)
  2. thyrotropic cells
    - secrete thyroid stimulating hormone (TSH) regulating thyroid gland secretion
  3. Corticotropic cells
    - secrete adrenocorticotropic hormone (ACTH)
    • stimulate adrenal cortex to secrete stress-related hormones and mediate metabolism
      - melanocyte-stimulating hormone (MSH)
    • stimulate melanocytes to produce melanin
  4. Gonadotropic cells
    - secrete follicle-stimulating (FSH) and luteinizing hormone that act on the gonads
  5. Mammotropic cells
    - secrete prolactin that stimulates milk productions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Hypothalamic-hypophyseal portal system

  • ANTERIOR PITUITARY
  • what does it consist of
  • steps

LO5

A

blood supply to ANTERIOR pituitary

Consist of primary capillary plexus, hypophyseal portal veins, and secondary capillary plexus

  1. When appropriately stimulated, hypothalamic neurons secrete releasing and inhibiting hormones into primary capillary plexus
  2. hypothalmic hormones travel through portal veins to the anterior pituitary where they stimulate or inhibit release of hormones made in anterior pituitary
  3. In response to releasing hormones, the anterior pituitary secretes hormones into secondary capillary plexus. This in turn empties into the general circulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Causes of gigantism and pituitary dwarfism

LO6

A

Gigantism

  • excess production of GH due to tumor
  • excessive bone growth, enlargement of extremities (acromegaly) and organs

Pituitary Dwarfs

  • hyposecretion of GH
  • normal body proportion but rarely 4 feet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Pineal Gland

  • location
  • microscopic organization
  • basic functions

LO7

A

out pocketing of diencephalon’s roof of 3rd ventricle

flatten cone-shaped 3-5mm diameter

fxn: growth, development, and circadian rhythms

cover with pia mater

synthesizes melatonin and serotonin

Consists of:

  • Pinealocytes
  • Neuroglia
  • Calcified granular material (brain sand) - calcium phosphate crystals located intercellular spaces showing up beginning early childhood
    • important radiogenic marker ( secreted by pinealocytes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Cell of Pars Distalis (anterior)
(4)

LO4

A
  1. Acidphils
    - somatotroph- GH
    - mammotrophs- prolactin
  2. Basophils
    - corticotrophs- ACTH
    - thyrotrophs- TRH
    - Gonadotrophs- FSH/ LH
  3. Chromophobes- unknown function
  4. Sinusoidal fenestrated capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Pars Intermidia

LO4

A
  • between pars distalis and pars nervosa
  • rudimentary in adults
  • unknown function
  • small basophils and colloid-filled follicles lined by cuboidal epithelium
  • Frequently has cleft (remnant of lumen and Rathke’s pouch)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pars Nervousa

LO4

A

continuous with median eminence of hypothalamus via infundibular stalk

  • does not manufacture hormones, rather stores adn releases them from axon terminals

consists of:

  1. hypothalamic unmyelinated axons
    - herring bodies- expanded axonal nerve terminals storing ADH/ oxytocin
  2. Pituicytes (glia-like) supporting the nerve fibers
  3. Fenestrated capillaries
22
Q

Pituitary Gland embryological origin

* supplement

A

from ECTODERM

Diverticulum-> diencephalon of neural tube-> infundibulum forms posterior and infundibular stalk and Rathke’s pouch forms rest of pituitary

23
Q

Infundibulum
-portion

LO4

A

suspend pituitary gland from hypothalamus

  1. Neural portion (infundibular stalk) - part of neurohypohysis connecting pars nervosa and median eminence of hypothalamus
    - unmyelinated axons ( nerve body in hypothalamus, terminals in pars nervosa)
  2. Adenhypophysis portion- surrounding pars tuberalis enveloping the infundibular stalk. May for a partial or total collar
    - consist of number cuboidal cells arranged in cords
24
Q

Hypothalamo-hypophyseal tract

  • Posterior Pituitary Gland
  • hormones
  • steps

LO5

A

Antidiuretic Hormone and Oxytocin

  1. Hypothalamic neurons synthesize oxytocin and ADH
  2. Oxytoxin and ADH are transported down the axons of hypothalmohyposeal tract to posterior pituitary
  3. Oxytoxin and ADH are stored in neurosecretory bodies in posterior pituitary
  4. When associated hypothalmic neurons fire, nerve impulses arriving at the neurosecretory bodies cause oxytoxin or ADH to be released into blood
25
Q

Thyroid Gland

  • location
  • blood supply
  • cells
  • hormones
  • function
  • importance

LO8

A

bi-lobed gland just below larynx and anterior to trachea

blood supply: from superior and inferior thyroid vessels

Cell types

  1. follicular cells
  2. Parafollicular C cells

Parts of the thyroid

  1. Thyroid follicle
  2. Follicle lumen

Hormones
- thyroid hormone

Target organs

  • hypothalamus
  • thyroid gland
  • kidney
  • bone

Function

  • control basal metabolism
  • control O2 usage
  • control body temperature
  • only gland to store hormone outside cell
26
Q

Follicular Cell

- cell types

A

simple cuboidal to columnar epithelium

many of them make follicles

they surround a fluid called colloid

27
Q

Colloid

- composition

A

thyroglobulin
- storage form of T3 and T4

  • must have iodine to activate
28
Q

Thyroid Hormone Synthesis and Turnover

- steps

A

made and stored in thryoglobulin

  1. thyroglobulin synthesized in RER, glycoslyated in golgi, secreted by EXOcytosis into lumen of follicle (colloid)
  2. Iodinated at apical surface forming T3 and T4 that remains to thyroglobulin
  3. TSH stimulates internalization of thyroglobulin via endocytosis where it is degrade, freeing T3 and T4
  4. T3 and T4 is released from basal surface of follicle cells into circulation
29
Q

Parafollicular Cells

- hormone

A
  • derived from neural crest cells

lie outside the follicle

secrete calcitonin when blood levels of calcium are high

lowers CA2+ in blood by:

  1. stimulating secretion by kidneys
  2. decreasing the calcium-releasing activity of osteoclasts
  3. increasing osteogenesis by osteoblasts
30
Q

Negative feedback loop for Hypothalmamic- Anterior Pituitary Thyroid Axis
- steps

A
  1. stimulus causes hypothalamus to secrete TRH -> acts on anterior pituitary
  2. Thyrotropic cells in anterior pituitary are stimulated to release TSH
  3. TSH acts on cells on thryoid gland. Follicular cells are stimulated to release TH
  4. TH stimulates target cells to increase metabolic activities=> increase in basal body temperature
  5. high TH levels=> increase heat production in cells=> inhibit TRH secretion
31
Q

Thyroid diseases

-list

A
  1. Grave’s disease
  2. Hypothyroidism
  3. Goiters
32
Q

Grave’s disease

  • describe
  • symptoms

LO9

A

abnormal antibodies stimulating TSH receptors causing over secretion of T3 and T4

symptoms

  • elevated metabolism
  • sweating
  • rapid HR
  • weight loss
  • protruding eyes

more common in women

33
Q

Hypothyroidism

  • describe
  • symptoms

LO9

A

insufficient T3 and T4
(opposite of graves)

symptoms

  • low metabolism
  • weight gain
  • lethargy
  • chillness
  • edema
  • mental sluggish
34
Q

Goiters
- describe

LO9

A

thyroid enlargement most commonly due to IODINE deficiency

follicle cells keep producing thyroglobulin but cannot iodinate it to make TH

35
Q

Parathyroid Glands

  • location
  • blood supply
  • cell types
  • main target organs and signficance

LO10

A

small ovoid glands
-posterior surface of thyroid gland

important in regulating serum calcium and phosphate levels (ESSENTIAL FOR LIFE)

blood supply: from superior and inferior thyroid vessels

cell types

  1. chief cells
  2. Oxyphil cell

Target organs

  • bone
  • kidney
  • intestine
  • bloodstream
36
Q

Chief principle cell

LO10

A

in parathyroid gland

release parathyroid hormone

secretion occurs when blood Ca2+ drops below normal and stops when levels return to normal

  • looks like nuclei
37
Q

Oxyphil Cells

A

unknown function

-looks like cytoplasm surrounding chief cells (nuclei)

38
Q

Calcium Regulation of PTH

A

if blood Ca2+ drops below 9.5 mg/dl=> Parathyroid releases PTH into bloodstream

  • increase osteoclast activity to resorb bone and release its calcium stores
  • increase calcium retention by kidneys
  • stimulates kidney to convert an inactive form of vit D to calcitriol (active vit D)
  • calcitriol increase calcium absorption by intestines

PTH will be inhibit when blood Ca2+ levels increases

39
Q

Adrenal glands

  • location
  • layers and secretion
  • cell types
  • hormones

LO11

A 
Adrenal Cortex (outer)
below capsule
1. zona glomerulosa
- secrete aldosterone
2. zona fasciculata
- secrete cortisol and androgens
3. Zona reticularis
- secrete cortisol and androgens

Medulla (inner core)
- secrete epinephrine and noepinephrine

40
Q

Adrenal Cortex

A

distinct yellow

secretes 25 steroid hormones (corticosteroids)

41
Q

Zona Glomerulosa

-hormone

A

in adrenal cortex

(mineralcorticoids)
- influence sodium and potassium levels

aldosterone

  • target kidney fxns
  • in response to low blood pressure or blood volume
  • controlled by RAAS
42
Q

Zona fasciculata

-hormone

A

in adrenal cortex

glucocorticoids

  • influence glucose metabolism and immune system
  • released under control of ACTH from anterior pituitary

Cortisol

  • deals with stress
  • mediates glucose metabolism
  • negative feedback mechanism for immune system
43
Q

Zona reticularis

A

in adrenal cortex

androgens

influence secondary sex characteristics

44
Q

Adrenal Medulla

A

inner core of each adrenal gland

consists of large, spherical cells (chromaffin cells)

when stimulated by ANS (SYMPATHETIC division) => secrete both epinephrine and noepinephrine

45
Q

Chromaffin Cells

- cell types

A

target of sympathetic neurons

  1. Epinephrine cells
    - smaller with granules less electron dense than NE cells
  2. Norepinephrine cells- larger with granules more electron dense
46
Q

Suprarenal Gland Syndromes

A
  1. Addison’s disease

2. Cushing’s syndrome

47
Q

Addison’s disease

LO12

A

HYPOsecretory disordder in glucocorticoids and mineralcorticoids

  • blood glucose and sodium levels drop
  • severe dehydration and low BP
  • fatigue
  • loss of apetite
  • autoimmune disease or inherited metabolic disease

RARE

48
Q

Cushing’s syndrome

LO12

A

hypersecretion of glucocorticoids bc of ACTH-secreting pituitary tumor or tumor in adrenal cortex

  • high serum glucose levels
  • protein loss in muscle
  • muscle weakeness
  • sweating
  • lethargy
  • fat distribution
49
Q

Pancreas Histology
-portions

LO13

A

Exocrine

  • glands
  • aids in digestion
  • organized in pancreatic acini

Endocrine

  • organized in pancreatic islets (langerhans)
  • scatteered amongst the exocrine cells
50
Q

Cells of Endocrine Pancreas
- describe

LO13 (list cells only)

A
  1. Alpha Cells
    - secrete glucagon when blood glucose levels drop
    - stimulates release of glucose from liver glycogen
  2. Beta Cells
    - secrete insulin when blood glucose levels are elevated
    - promote glycogen storage in liver and entry into cells
  3. Delta cells
    - secrete somatostatin (slows insulin and glucose release)
    - control rate of nutrient entry into bloodstream and acell
    - stimulated by high levels of nutrients and in bloodstream
  4. F cells
    - secrete pancreatic polypeptide that inhibit somatostatin release
51
Q

Pancreatic Blood Supply

A
  1. Insuloacinar portal system
    - supply islets of langerhand and pancreatic acini
    - enable local action of exocrine pancreas of hormones
  2. Acinar vascular system
    - independent arterial supply
    - supply pancreatic acini
52
Q

Other endocrine organs/cell

LO14

A
  1. gonads- estrogen, testosterone, progesterone
  2. Heart- atrial natriuretic peptide
  3. GI tract- peptides regulating digestion (gastrin and secretin)
  4. placenta- estrogen, progesterone, HCG
  5. Kidney- renin, erythropoietin
  6. Skin- precursor to vitamin D

Endo Repro Midterm (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions