Brainscape's Knowledge GenomeTM

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


See full index

Neuro Endo 3 > Histology of Endocrine Organs > Flashcards

Histology of Endocrine Organs Flashcards

1
Q

Nervous System

A
  • membrane depolarization and transmission of signal from synapses
  • communication is rapid but effects on target cell/organs is short lived
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Endocrine System

A
  • involves chemicals (hormones) distributed throughout the body by cardiovascular system
  • bind to specific receptors on “target cells”
  • slower communication, but longer duration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Humoral stimuli

A
  • release controlled by monitoring levels of ions and nutrients in blood and body fluids
  • I.e. release of parathyroid hormone stimulated by low serum calcium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Neuronal stimuli

A
  • release stimulated by nerve signals

- I.e. release of epi from adrenal gland in response to sympathetic nerve fibers

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

Hormonal stimuli

A
  • release caused by hormone secreted into bloodstream by another endocrine organ or cell
  • I.e. release of thyroid hormone stimulated by the release of TSH from pituitary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Characteristics of endocrine gland organization

A
  • epithelioid cells arranged as cords/follicles (some isolated as individual cells)
  • derived from epithelia
  • well vascularized
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the hypothalamus directly influence the anterior pituitary gland?

A

Produces releasing hormones and inhibiting hormones that directly influence pituitary hormone secretion

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

How does the hypothalamus directly influence the kidney and uterus?

A

Produces two hormones (oxytocin and antidiuretic hormone) that are stored in the posterior pituitary

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

How does the hypothalamus directly influence the adrenal medulla?

A

Oversees the ANS, helping to stimulate adrenal medulla via sympathetic innervation

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

How do hypothalamic hormones indirectly influence the body?

A

Releases hormones (tropic hormones) that stimulate or inhibit release of other hormones from the anterior pituitary

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

What parts of the body do hypothalamic hormones indirectly influence?

A

Thyroid gland- thyroid stimulating hormone (TSH)
Adrenal gland- adrenocorticotropic hormone (ACTH)
Mammary gland- prolactin
Gonads- follicle stimulating hormone (FSH) and lutenizing hormone (LH)
Bone/other organs- growth hormone (GH)
Melanocytes- melanocyte stimulating hormone (MSH)

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

What is the pituitary gland formed from and in what week?

A

Ectodermal placode leading to Rathke’s pouch

Week 3

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

What occurs with the pituitary gland during week 8 in utero?

A
  • pouch loses connection with outside
  • joins diverticulum from developing diencephalon of neural tube
  • infundibulum forms posterior pituitary and infundibulum stalk
  • Rathke’s pouch forms rest of pituitary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does anterior pituitary come from?

A

-ectoderm from oral cavity

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

Where does posterior pituitary come from?

A

-neural ectoderm from developing diencephalon

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

What weeks are the following hormones developed: ACTH, GH, TSH & LH, FSH

A

ACTH- 7 wks
GH- 8 to 9 wks
TSH & LH- 12 wks
FSH- 13 wks

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

What cell type compromises the anterior pituitary gland? What are these cells controlled by?

A

glandular epithelial cells controlled by neurohormones released from hypothalamus

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

How much of the pituitary gland is considered anterior?

A

80%

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

What is the posterior pituitary comprised of?

A
  • axons from hypothalamus that carry ADH and oxytocin for storage and release
  • support cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Parts of anterior pituitary (adenohypophysis)

A 
Pars tuberalis (surrounds infundibulum)
Pars intermedia (between posterior and anterior)
Pars distalis (big circular part of anterior pituitary)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Parts of posterior pituitary (neurohypophysis)

A 
Infundibular stalk (connection to hypothalamus)
Pars nervosa (big circular part of posterior pituitary)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Major cell types in Anterior Pituitary

A 
Somatotropic
Thyrotropic
Corticotropic
Gonadotropic
Mammotropic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Function of Somatotropic cells (ant. pit)

A

secrete GH

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

Function of Thyrotropic cells (ant. pit)

A

secrete TSH regulating thyroid gland secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Function of Corticotropic cells (ant. pit)

A
  • secrete ACTH which stimulates adrenal cortex to secrete stress related hormones and mediate metabolism
  • secrete MSH which stimulates melanocytes to produce melanin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Function of Gonadotropic cells (ant. pit)

A

secrete FSH and LH that act on gonads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Function of Mammotropic cells (ant. pit)

A

secrete prolactin and stimulate milk production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Cells of Pars Distalis (anterior pituitary)

A

Acidphils
Basophils
Chromophobes
Sinusoidal (fenestrated) capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Cell types within acidphils

A

Somatotrophs- GH

Mammotrophs- Prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Cell types within basophils

A

Corticotrophs- ACTH
Thyrotrophs- TSH
Gonadotrophs- FSH/LH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the pars intermedia and what does it do?

A
  • Part of the anterior pituitary between the pars distalis and pars nervosa
  • Contains small basophilas and colloid-filled follicles lined by cuboidal epithelium
  • Frequently contains cleft = remnant of Rathke’s pouch
  • Unknown function (rudimentary in adults)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where is the pars nervosa located?

A

Part of the anterior pituitary continuous with median eminence of the hypothalamus via infundibular stalk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the function of the pars nervosa?

A

Stores and releases hormones from axon terminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the pars nervosa comprised of?

A
  • hypothalamic unmyelinated axons (Herring bodies = expanded axonal nerve terminal storing ADH/oxytocin)
  • pituicytes (glia-like) support nerve fibers
  • fenestrated capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Describe the hypophyseal portal system

A
  • blood supply to the hypophysis

- hypothalamic hormones are released into this blood system to control the release of anterior pituitary hormones

36
Q

What are the components of the portal system?

A

1) Primary capillary plexus- where hypothalamic neurons secrete releasing or inhibiting hormones
2) Hypophyseal portal veins- hormones travel through portal veins to anterior pituitary to stimulate or inhibit hormone release
3) Secondary capillary release- where the hormones secreted from the anterior pituitary travel into the general circulation

37
Q

Hormones released from anterior pituitary

A

FLAT PeG

FSH, LH, ACTH, TSH, Prolactin, endorphins, GH

38
Q

Hormones released from posterior pituitary

A

ADH, oxytocin

  • transported down axons to posterior pituitary
  • stored in neurosecretory bodies in posterior pituitary
  • when hypothalamic neurons fire, nerve impulses arriving at neurosecretory bodies cause oxytocin to be released into blood
39
Q

Function of ADH

A

Targets kidney to regulate sodium and water retention

40
Q

Function of Oxytocin

A

Targets uterine smooth muscle and stimulates lactation; induces birth
May be involved in sexual arousal and pair and social bonding

41
Q

Origin of pineal gland

A

out pocketing of diencephalon’s roof of 3rd ventricle

covered in pia mater

42
Q

Function of pineal gland

A

Growth, development, circadian rhythm, synthesizes melatonin and serotonin

43
Q

What is the pineal gland comprised of?

A
  • pinealocytes
  • calcified granular material = calcium phosphate crystals located intercellular spaces showing up beginning in early childhood (important radiogenic marker)
  • neuroglia
44
Q

Characterize the anatomy of the thyroid

A

-follicles consisting of follicular cells surrounding a fluid called colloid

45
Q

What type of cell are the follicular cells?

A

simple cuboidal to columnar epithelium

46
Q

What does the colloid fluid contain?

A

Thyroglobulin = storage form of thyroid hormones T3 and T4

47
Q

What is the only gland to store hormone outside the cell?

A

Thyroid

48
Q

What are the functions of thyroid hormones?

A
  • control metabolism
  • O2 usage
  • body temperature
49
Q

Where is thyroid hormone generated and stored?

A

Extracellularly as thyroglobulin

50
Q

Synthesis of thyroglobulin

A
  • synthesized in the rER
  • glycosylated in Golgi
  • secreted by exocytosis into lumen of the follicle
  • iodinated at apical surface forming T3 and T4 that is bound to thyroglobulin
51
Q

What does TSH stimulate?

A

Internalization of thyroglobulin via endocytosis where it is degraded, freeing T3 and T4

52
Q

How are T3 and T4 released?

A

Released from basal surface of follicle cells into the circulation

53
Q

Where are parafollicular cells located?

A

Lie just outside the follicles of the thyroid

54
Q

Function of parafollicular cells

A

Secrete calcitonin when blood levels of calcium are HIGH

55
Q

How does the release of calcitonin from parafollicular (C) cells lower circulating calcium?

A
  • stimulates kidney secretion
  • decreases the calcium releasing activity of osteoclasts
  • increases osteogenesis by osteoblasts
56
Q

What disease is caused by abnormal antibodies stimulating TSH receptors and causing an overproduction of T3 and T4?

A

Grave’s Disease (1:2000 in US)

57
Q

What are the symptoms of Grave’s disease?

A
  • elevated metabolism
  • sweating
  • rapid heart rate
  • weight loss
  • eyeballs protruding
  • more common in women
58
Q

Hypothyroidism mechanism

A

Insufficient T3 and T4 production

Often autoimmune disease-causing follicle cell death

59
Q

Symptoms of hypothyroidism

A
  • low metabolic rate
  • weight gain
  • lethargy
  • chilliness
  • edema
  • mental sluggish
60
Q

Treatment for Grave’s Disease

A

Thyroidectomy or anti-thyroid drugs

61
Q

Treatment for hypothyroidism

A

synthetic T3/T4

62
Q

What is the result of iodine deficiency

A

Goiters

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

63
Q

Where are parathyroid glands located?

A

posterior surface of thyroid gland

64
Q

What does parathyroid gland release?

A

Parathyroid hormone (PTH)

65
Q

Function of parathyroid glands?

A

Regulate serum calcium and phosphate levels

66
Q

What are the two cell types of parathyroid gland?

A

Chief (principle) cells

Oxyphil cells

67
Q

What are the functions of chief cells in the parathyroid gland?

A
  • release PTH
  • secretion occurs when blood calcium falls below normal range (9.5-10.5 mg/dL)
  • secretion stops when level of calcium returns to normal
68
Q

Steps of calcium regulation by PTH

A

1) low blood calcium levels
2) PTH secreted into bloodstream
3) stimulates osteoclasts to resorb bone and release calcium; increase calcium retention by kidneys; stimulates kidney to convert an inactive form of vitamin D to calcitriol (active) which increases calcium absorption by the intestines
4) Blood calcium levels increase and inhibit further PTH release

69
Q

How is the adrenal gland divided?

A

Outer adrenal cortex

Inner central core = adrenal medulla

70
Q

Name the layers of the adrenal gland and the hormone it secretes from top to bottom.

A 
Capsule
Zona glomerulosa- aldosterone
Zona fasciculata- cortisol and androgens
Zona reticularis- cortisol and androgens
Adrenal medulla- epi and norepi
71
Q

What kind of hormones are secreted from the adrenal cortex that are vital for survival?

A

steroid hormones (corticosteroids)

72
Q

What are the structures and functions of the 3 zones of the cortex?

A

1) Zona glomerulosa (mineralocorticoids)- influence sodium and potassium levels; releases aldosterone
2) Zona fasciculata (glucocorticoids)- influence glucose metabolism and immune system; released under control of ACTH from anterior pituitary; releases cortisol
3) Zona reticularis (androgens)- influence secondary sex characteristics

73
Q

Function of aldosterone

A
  • targets kidney
  • secreted in response to low BP or BV
  • controlled by renin-angiotensin system
74
Q

Function of cortisol

A
  • deals with stress and mediates glucose metabolism

- serves as negative feedback mechanism for the immune system

75
Q

What does the adrenal medulla consist of?

A

Clusters of large, spherical chromaffin cells which are the target of sympathetic neurons

76
Q

What do chromaffin cells secrete when stimulated by the sympathetic division of ANS?

A

epi- smaller with granules less electron dense

norepi- larger with granules more electron dense

77
Q

Addison’s Disease

A

HYPOsecretory disorder in both glucocotricoids and mineralcorticoids

78
Q

Symptoms of Addison’s

A
  • low blood glucose
  • low blood sodium
  • severe dehydration
  • low BP
  • fatigue
  • loss of appetite
79
Q

Cushing’s Syndrome

A

HYPERsecretion of glucocorticoids because of either an ACTH secreting pituitary tumor or a tumor in adrenal corte

80
Q

Symptoms of Cushing’s Syndrome

A
  • high serum glucose levels
  • protein loss in muscles
  • muscle weakness
  • lethargy
  • depression of immune system
  • buffalo hump and moon face
81
Q

Parts of the pancreas

A

Exocrine cells organized in pancreatic acini

Endocrine cells organized into clusters called pancreatic islets

82
Q

Pancreatic Alpha cells

A

Secrete glucagon when blood glucose levels drop; stimulates release of glucose from liver glycogen stores

83
Q

Pancreatic Beta cells

A

Secrete insulin when blood glucose levels are elevated and promotes glycogen storage in liver and entry into cells

84
Q

Pancreatic Delta cells

A

Secrete somatosatin, slowing the release of insulin and glucagon thereby controlling the rate of nutrient entry into the bloodstream and cells; stimulated by high levels of nutrients in blood stream

85
Q

Pancreatic F cells

A

Secrete pancreatic polypeptide that inhibit the release of somatosatin

86
Q

Pancreatic blood supply

A

1) insuloacinar portal system supplies each islet of langerhans
2) acinar vascular system supplies the pancreatic acini

Neuro Endo 3 (13 decks)

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