Endocrine System Flashcards
cells that produce steroid hormones contain a lot of what type o structure?
smooth ER
ductless glands that secrete their products internally
Endocrine Glands
what are the two types of hormones?
circulating
Local
What are the two types of Local Hormones
Paracrine
Autocrine
Hormones that act on neighboring cells
Paracrine Hormones
Hormones that act on the same cells that is is secrete from
Autocrine Hormones
Hormones that are secreted into the circulatory system and act on any cell that has the appropriate receptor
circulating hormones
what does the the pineal gland secrete?
melatonin
Where are antidiuretic hormone and oxytocin made
Hypothalamus
What does the thyroid secrete
calcitonin
thyroid hormone
Where are antidiuretic hormone and oxytocin secreted from
Posterior Pituitary
what is the embryological origin or the diencephalons
prosencephalon
what secondary vesicle does the hypothalamus originate from?
diencephalons
main visceral (autonomic) control center for the body
Hypothalamus
the secretions from this gland can regulate other glands
Hypothalamus
What connects the hypothalamus to the Posterior Pituitary
The infundibulum
what two glands regulate virtually all aspects of growth, development, metabolism, and homeostasis
the hypothalamus and the pituitary gland (hypophysis)
master gland for the endocrine system
pituitary gland (hypophysis)
How many hormones does the Hypothalamus produce?
9
What gland is considered Command Center for Endocrine System
Hypothalamus
to see the relationship between the hypothalamus and the the pituitary gland what section should the brain be viewed?
Sagittal
Where is the pituitary gland located in relation to the nasal cavity?
posterior corner of the roof
Where does the pituitary gland sit?
hypophyseal fossa or sella turcica of sphenoid bone
Cords of epithelial cells interspersed with fenestrated capillaries in the anterior pituitary
Pars Distalis
A series of colloid-filled follicles in the anterior pituitary
Pars Intermedia
What represent the residual lumen of Rathke’s pouch
colloid-filled follicles
What part of the anterior pituitary gland forms a collar or sheath around infundibulum
Pars Tuberalis
most of the cells in the ___ are basophilic gonadotropic cells
Pars Tuberalis
Contains neurosecretory axons and their endings from the hypothalamus
Pars Nervosa
Regulating hormones from the hypothalamus reach the anterior lobe via the
hypothalamo-hypophyseal portal system
where hormones travel down the axons of the neurosecretory cells to the axon terminals where they exit via exocytosis
hypothalamic
Human growth hormone is secreted from what type of cells
Somatotropes
Thyroid-Stimulating Hormone is secreted from what type of cells
Thyrotropes
Follicle-Stimulating Hormone is secreted from what type of cells
Gonadotropes
Luteinizing Hormone is secreted from what type of cells
Gonadotropes
Prolactin is secreted from what type of cells
Lactotropes
Adrenocorticotrophic is secreted from what type of cells hormone
Corticotropes
Melanocyte-Stimulating Hormone is secreted from what type of cells
Corticotropes
what type of cell are Corticotropes
Basophil - Chromophil
what type of cell are Lactotropes
Acidophil - Chromophil
what type of cell are Gonadotropes
Basophil - Chromophil
what type of cell are Thyrotropes
Basophil - Chromophil
what type of cell are Somatotropes
Acidophil - Chromophil
Chromophobes and Chromophils make up half the cell population in what?
Pars distalis
Reserve of primitive/ undifferentiated cells in the Pars Distalis
Chromphobes
Where is the hormone stored in Chromophils
cytoplasmic granules
Least numerous cell but they have the most numerous cell types
Basophils
powerful cells where a little bit goes a long way
basophils
what regulates the anterior pituitary gland?
Hypothalamus
what regulates all other glands
Anterior Pituitary
which if the chromophils is most active
acidophil
stimulates the release of Melanocyte-stimulating hormone
Corticotropin-releasing hormone
suppresses the release of Melanocyte-stimulating hormone
Dopamine (Prolactin- inhibiting hormone)
stimulates the release of Adrencoritcotropic hormone (ACTH)
Corticotropin-releasing hormone
suppresses the release of prolactin
Prolactin- inhibiting hormone (Dopamine)
stimulates the release of Follicle stimulating hormone
Gonadotropin-releasing hormone
stimulates the release of Luteinizing hormone
Gonadotropin-releasing hormone
stimulates the release of Thyroid-stimulating hormone
Thyrotropin- releasing hormone
suppresses the release of Thyroid-stimulating hormone
Growth hormone- inhibiting hormone
suppresses the release of Human growth hormone
Growth hormone- inhibiting hormone
stimulates the release of Human growth hormone
Growth hormone- releasing hormone
Growth hormone- releasing hormone is also known as
somatocrinin
Which f the chromophilis has a granular appearance
Basophils
Initiates the development of oocytes
Follicle-stimulating hormone
Induces ovarian secretion of estrogen
Follicle-stimulating hormone
Stimulates testes to produce sperm
Follicle-stimulating hormone
Promotes growth of body cells, protein synthesis, tissue repair, lipolysis and elevation of blood glucose concentration
Human-growth hormone
(along w/ other hormones) promotes milk secretion
Prolactin
stimulates ovulation
Lutenizing hormone
when a section of the pituitary gland is prepared what two sections remain together if the tissue splits
Pars Nervosa
Pars Intermedia
A collar or sheath wrapping around the the pituitary gland stalk
Pars tuberalis
What are the two hormones produced in the hypothalamus and secreted by the posterior pituitary gland
oxytocin (OT) antidiuretic hormone (ADH) (vasopressin)
what causes the dilation at the axon terminals in the Pars nervosa
hormones stored in secretory vesicles
dilated portions of the axons near the terminals in the Pars nervosa
Herring bodies
Another name for Herring bodies
neurosecretory bodies
A type of glial cell, resembling the astrocyte, that associates with the fenestrated capillaries
pituicytes
most common cell type in posterior pituitary
pituicytes
Does the posterior pituitary lobe have secretory cells?
No
Does the posterior pituitary lobe synthesis hormones?
No
Uterus destination and nipple stimulation, stimulates the secretion of ___ form the ___
Oxytocin, Hypothalamus
Elevated blood osmotic pressure, dehydration, loss of blood volume, pain, or stress stimulates the secretion of ___ from the _____
ADH, Hypothalamus
Low blood osmotic pressure, high blood volume and alcohol inhibits the secretion of
ADH
Stimulates smooth muscles contraction of the uterus and myoepithelial cells in the mammary glands
Oxytocin
What type of gland is the pineal gland
Neuroendocrine
What does the pineal gland regulate?
circadian rhythm
What is the major secretion for the pineal gland
melatonin
In a histological slide what is a distinguishing characteristic of the pineal gland
Coropa arenacea (brain sand)
Two types of cells in the pineal gland
Pinealocytes (parenchymal cells)
Interstitial (Glial) cells
Three layers of the adrenal gland
fibers capsule
Cortex
Medulla
Contains catecholamine-secreting cells
Adrenal Medulla
Contains steroid-secreting cells
Adrenal Cortex
Is the Adrenal cortex or medulla larger?
cortex
Which of the adrenal layer has large vessels
medulla
Where do the adrenal veins drain into?
Caval stystem
cytoplasm has a foamy appearance in a histological stain
Zona fasciculata
Same the zones in the adrenal cortex from capsule to medulla
Zona glomerulosa
Zona fasciculata
Zona reticularis
The thickest of the three adrenal cortex regions. it contains cells that are arranged in long cords/rows
Zona fasciculata
What does the Zona glomerulosa secrete
Mineralocorticoids, mainly Aldosterone
What does the Zona fasciculata secrete
Glucocorticoids, maily cortisol
What does the Zona reticularis secrete
Androgens
What does the adrenal medulla secrete
Epinephrine and Norepinephrine
where are presynaptic sympathetic nerves located in the adrenal gland
Medulla
where do hormones collect to be cent out into the body
Central vein
where is the central vein located
in the medulla
Main function of aldosterone
regulates Na+, K+ and water (control of blood pressure)
Main function of Cortisol
Regulates glucose and fatty acid metabolism. Provides resistance to stress and suppresses immune function
Main function of Androgen (DHEA)
Axillary pubic hair in both sexes
What intensifies sympathetic response in other body parts
Epinephrine and norepinephrine
Epinephrine and norepinephrine are what
Catecholamines
which gland is developed form neural crest cells?
Adrenal Medulla
controlled by sympathetic preganglionic neurons in the medulla
Chromaffin cells
Allows for quick signally to the chromaffin cells to release hormones via exocytosis
sympathetic preganglionic neurons
cluster around blood vessels & release hormones
Chromaffin cells
In a histological section how can you identify Chromaffin cells
they area associated with blood vessels
The endocrine portion of the pancreas
islets of Langerhans
Where are the islets of Langerhans most numerous
in the tail
The three principle cells of the islets of Langerhans
Beta (B cells)
Alpha (A ells)
Delta (D cells)
Secretes insulin
Beta (B) cells
Secretes glucagon
Alpha (A) Cells
Secretes somatostatin
Delta (D) cells
Where does the tail on the pancreas point?
Hilum of the spleen
lowers blood glucose level as it signals for an acceleration of glucose transport into cells and the conversion of the glucose into glycogen
Insulin
Associated with glycogenesis
Insulin
raises blood glucose level as it signals for the acceleration of the breakdown of glycogen into glucose in the liver
Glucagon
Associated with glycogenolysis
Glucagon
Inhibits insulin and glucagon secretion
Somatostatin
what creates lobes in the thyroid gland
fibrous capsule & septa
control of basal metabolic rate and oxygen consumption of body cells
T3 and T4
Four atoms of iodine
Thyroxine
Three atoms of iodine
Tri-iodothyronine
Follicles contain colloid which is a gel-like mass predominantly composed of
thyroglobulin
inactive form of the thyroid hormones
thyroglobulin
Where is thyroglobulin modified
follicular cells
How is thyroid hormone released
fenestrated blood capillaries that surround the follicles
May be part of the follicular epithelium or found between the follicles of the thyroid gland
Parafollicular cells (C cells)
Produce the hormone calcitonin
Parafollicular cells (C cells)
Decreases the level of calcium in the blood by encouraging calcium salts to be deposited in bone matrix
calcitonin
Inhibits the action of osteoclasts
calcitonin
How is the secretion of calcitonin regulated
Negative feed back
What stimulate the release of calcitonin
high blood levels of Ca2+
what is located in the posterior surface of the thyroid gland
Parathyroid
How many parathyroid glads are normally present?
4 (2-6)
produce parathyroid hormone (PTH)
Chief cells
more common with age
Oxyphil cells
2 cell types located in the parathyroid glands
Oxyphil cells
Chief cells
Most numerous cell in the parathyroid
Chief cells
Increases the level of calcium in the blood stimulation of osteoclasts
parathyroid hormone (PTH)
How does PTH impact the kidney?
Slow the rare id Ca2+ released into the urine
