Chapter 6: Endocrine System Flashcards
Influences the metabolic processes of the body.
Hormones
Are scattered throughout the body.
Endocrine glands
The glands are _______ thus, hormonal secretions are poured directly to the blood through the capillaries.
Ductless
The internal supporting framework of the endocrine glands
Reticular tissue
The endocrine gland is ________, thus provided with rich capillary networks among and between groups of secretory cells.
Highly vascular
The capillaries are _________ in which endothelial wall contains numerous pores or openings which are covered by very thin ________.
Fenestrated type. Diaphragms.
Development of endocrine system are from what origins.
Ectodermal, Mesodermal & Endodermal
Ectodermal in origin
Pituitary gland, Adrenal medulla & Pineal gland “PAP”
Mesodermal in origin
Leydig cells of the testes, Adrenal cortex & Theca internal cells of the ovary “LAT”
Endodermal in origin
Thyroid gland, Islets of Langerhans, Parathyroid gland & Parafollicular cells or C-cells “TIPP”
Pituitary gland develops from what sources
Infundibulum & Rathke’s pouch
Primitive of mouth cavity
Stomodeum
Ectodermal outpocketing of the stomodeum. Gives rise to adenohypophysis.
Rathke’s pouch
Anterior wall of the Rathke’s pouch gives rise to
Pars distalis & Pars tuberalis
Posterior wall of the Rathke’s pouch gives rise to
Pars intermedia
Downward extension of the diencephalon. Gives rise to neurohypophysis.
Infundibulum
Neurohypophysis is composed of
Pars nervosa(infundibular process), Infundibular stem/stalk & Median eminence of tuber cinereum “PIM”
Other name for pituitary gland
Hypophysis cerebri
_______ is a pea shaped glandular organ lodged in the _______ of the ________ of the body of the _______.
Hypophysis. Hypophyseal fossa. Sella tursica. Sphenoid.
Pituitary gland is connected by the _______ stalk to the base of the brain and is covered by a capsule of ________.
Infundibulum. Dense connective tissue.
Divisions of the hypophysis
Neurohypophysis & Adenohypophysis
Posterior part developed as a downgrowth from the floor of the __________.
Neurohypophysis. Diencephalon.
Anterior part derived from the Rathke’s pouch. An outgrowth from the __________ of the primitive oral cavity.
Adenohypophysis. Ectodermal roof.
Subdivisions of the Adenohypophysis
Pars Tuberalis, Pars Intermedia & Pars Distalis “TID”
Largest subdivision of adenohypophysis
Pars distalis
2 grouped categories of the cell in Pars distalis
Chromophobes & Chromophils
In chromophils, 2 types of cells based on affinity to stains
Acidophils & Basophils
Acidophils secrete
Prolactin & GH “PG”
Basophils secrete
FSH, LH, ACTH & TSH “FLAT”
Smallest and least numerous among the cells in the pars distalis. Since they are _____, their nuclei lie close to each other; and their cytoplasm is ______, thus hardly seen.
Chromophobes. Small. Scanty.
Chromophobes are also referred as ________, since some of them may differentiate into acidophils & basophils as the need arises.
Reserve cells
It is the most highly vascular portion of the hypophysis. It is formed of ___________ of cells that descend towards the pars distalis.
Pars tuberalis. Longitudianl column/cords.
No hormone isolated in this subdivision
Pars tuberalis
Cell types of the Pars tuberalis
Undifferentiated cells & Small basophils & acidophils
It is found between the pars distalis and the infundibular process. It is characterized by presence of _______ filled with colloid and lined by ______ epithelium, which are called ________.
Pars Intermedia. Follicles/Cyst. Columnar. Rathke’s cyst.
Hormone that causes the dispersion of melanin pigments in the ______ and increases the pigmentation of the skin. Secreted by?
Melanocyte Stimulating hormone. Melanoblast. Pars Intermedia.
Cells that are also found in the Pars Intermedia.
Polygonal Basophilic cells
It is formed of venules that connectbthe capillaries in the median eminence with the capillary sinusoids in the pars distalis.
Hypophyseal system
The ________ from the hypothalamus reach the pars distalis through _______.
Neurohormone. Nerve fibers.
The blood supply of the hypophysis is delivered from the _________, which are branches of
Superior hypophyseal arteries. Internal carotid & PCA.
It is thru the ________ that the releasing hormones from the hypothalamus reach the secretory cells of the pars distalis.
Hypophyseal portal circulation
Is formed of unmyelinated nerve fibers of the hypothalamo-hypophyseal tract, which are formed of axons of the neurons in the hypothalamic nuclei.
Neurohypophysis
In neurohypophysis, the axons descend through the _______ to the ________ and __________.
Median eminence. Infundibular stalk. Infundibular process.
Also found in the neurohypophysis, part of the pars nervosa. Cells with numerous processes and are considered as modified neuroglial cells.
Pituicytes
Are small, spherical structures containing neurohormones stored in pars _______ or in the infundibular process. These are neurosecretory materials secreted by the neurons in the hypothalamic nuclei and travel along the axons of these neurons to be stored and released from the ________ of the nerve fibers.
Herring bodies. Pars nervosa. Axolemma.
Hormones in the Pars nervosa
Pitocin(oxytocin) & Pitressin(ADH)
Secreted by the supraoptic nuclei of the hypothalamus. Increase water retention.
ADH (Pitressin)
Secreted by the paraventricular nuclei of the hypothalamus. Stimulates uterine contraction.
Oxytocin(Pitocin)
The gland is found in the anterior part of the neck, consisting of two lobes connected by a narrow _______, which crosses the trachea just below the cricoid cartilage.
Thyroid gland. Isthmus.
In thyroid gland, it has a _________ capsule that is continuous with the surrounding _________. The outer capsule is loosely adherent on its deep surface of another layer of moderately dense connective tissue that is intimately adherent to the gland.
Connective tissue. Cervical fascia.
The thyroid gland develops from the proliferation in the floor of the ________ between the ________ & _______, at a point layer indicated by the _________.
Pharynx. Tuberculum impar & copula. Foramen cecum.
The thyroid gland descends in front of the pharyngeal gut as a ________. This is connected to the tongue by a narrow canal, the ________, which later disappears.
Bilobed diverticulum. Thyroglossal duct.
In thyroid gland, the cystic remnants of the thyroglossal duct is called
Thyroglossal cyst
In thyroid gland, this gives rise to the ultimobranchial body, which later is incorporated in the thyroid gland.
5th pharyngeal pouch
The cells of the ultimobranchial body give rise to ____________ of the thyroid gland secreting _________.
Parafollicular/C-cells. Calcitonin.
The structural unit of the thyroid gland is the __________, which are lined by _______ and containing gelatinous _________. This represents the stored product of the secretory activity by the lining epithelium.
Spherical cystlike follicles. Simple cuboidal epithelium. Colloid.
The follicular cells are surrounded by a
Thin basal lamina
In the thyroid gland, the epithelial cells vary in height, but are commonly _______, ______ when the gland is hypoactive, _______ when it is hyperactive.
Cuboidal. Squamous. Columnar.
In the thyroid gland, nucleus is _______, _______ located, poor in ______ and contain _______ nuclei.
Spherical. Centrally. Chromatin. One or more nuclei.
Aside from the follicular cells, there are cells which are found singly or in groups wedged between the follicular cells and the lamina or between the thyroid follicles known as
Parafollicular cells
Parafollicular cells named based on its position, but with the discovery that they produce ________, they are now called ______. Other names are
Calcitonin. C-cells. Light cells, Mitochondria-rich cells & Ultimobranchial cells.
Decrease blood calcium level by the ______ or parafollicular cells through the secretion of _______.
Thyroid gland. C-cells. Calcitonin.
Synthesize, store and release hormones concerned with the regulation of metabolic by the follicular epithelial cells.
Thyroid gland
Hormones secreted in the thyroid gland are
Triiodothyroxine(T3) & Tetraidotyroxine(T4)
Development of the parathyroid gland: from the dorsal wing of the 3rd pharyngeal pouches.
Inferior parathyroid
Development of the parathyroid gland: from the dorsal wing of the 4th pharyngeal pouches.
Superior parathyroid
These are two pairs of glands which are small, __________ adhering to the posterior surface of the thyroid gland. A ________ separates them from the thyroid gland.
Parathyroid gland. Yellow-brown oval bodies. Connective tissue capsule.
Delicate __________ partially divide the gland into poorly definend lobules and still finer ones separate the epithelial cells into anastomosing cords & groups.
Connective tissue septa
The parenchyma of the parathyroid gland is composed of two types of cells
Oxyphil cells & Principal/Chief cells
Constant occurrence. Polyhedral cells with round nuclei, with loosely arranged chromatin giving a vesicular appearance, and basophilic cytoplasm.
Principal/Chief cells
Shape of Chief cells
Polyhedral w/ rounded nuclei
Cytoplasm of Principal cells
Basophilic
Appear only at the end of the first decade of life until puberty. Larger cells with smaller and darker nuclei and acidophilic cytoplasm.
Oxyphil cells
Size of oxyphil cells
Larger cells
Nuclei of oxyphil cells
Small and darker nuclei
Cytoplasm of the oxyphil cells
Acidophilic
Regulate calcium concentration by stimulating resorption of bone and reabsorption of calcium ions from ultrafiltration of the kidneys and with the aid of _______ absorption of calcium from the gut.
Parathyroid gland. Vitamin D.
Through the _______ secretion of _______, blood calcium level increases.
Principal cell. PTH.
About the ___ of development, mesothelial cells proliferate and later differentiate into large acidophilic structures forming the ___________ of the adrenal gland.
Adrenal cortex. 5th week. Primitive Fetal Cortex.
In adrenal cortex, shortly later a second wave of cells from the ________ penetrate and surround the original acidophilic mass. These cells will form the ________ of the adrenal gland.
Mesothelium. Definitive cortex.
Arises from the _________ cell. These cells invade the medial aspect and become cords and clusters forming the
Neural crest. Medulla of the adrenal gland.
The cells of the adrenal medulla are stained _________ with ________. Hence they are called _________.
Yellowish brown. Chrome salts. Chromaffin cells.
Are roughly triangular, flattened organs embedded in the retroperitoneal fat tissue at the cranial pole of each kidney.
Adrenal or Suprarenal glands
The adrenal gland has a ______ capsule of connective tissue that extends into the cortex as ________.
Thick. Trabeculae.
The adrenal glands has two functionally and structurally distinct parts
Cortex & Medulla
The principal secretory cells of the medulla are derived from the
Neural crest cells
The secretory cells of the cortex are derived from the
Mesodermal cells in the nephrogenic ridge
Forms the bulk of the gland.
Adrenal cortex
The adrenal cortex has three distinguishable concentric zones
Zona glomerulosa, Zona Fasciculata & Zona Reticularis
The middle and broadest zone is composed of cell cords coursing _______ to one another in ______ toward the medulla.
Zona fasciculata. Parallel. Radial.
In zona fasciculata, the secretory cells are ______ or _______ and sometimes ________, which are ________.
Cuboidal/polyhedral. Binucleated. Vesicular.
It produces aldosterone
Zona glomerulosa
Adjacent to the capsule is a narrow zone in which the cords of _________ are in _______ groups.
Zona glomerulosa. Columnar cells. Ovoid.
there is ___________ within a cell group as in exocrine glands, but there is a rich network of blood vessels externally.
Zona glomerulosa. No central cavity.
A potent mineralocorticoid causing water and sodium retention im exchange for potassium in the kidney.
Aldosterone
Network of cell cords, which are smaller than those of the fasciculata, _______ nuclei, fewer lipid droplets and numerous ___________.
Zona reticularis. Darker. Lipofuschin.
The major products of zona reticularis
Glucocorticoids(cortisol) & Dehydroepiandrosterone(androgen)
The most important glucocorticoid, has a protein wasting effect and promotes __________.
Cortisol. Gluconeogenesis.
It is probable that the ___________ produces much of the cortisol in unstressed individuals.
Outer part of the fasciculata
The secretory cells here are in anastomosing groups associated with blood vessels. The parenchymal to _______, and contain _________, which become brown when oxidized by __________.
Adrenal medulla. Columnar. Cytoplasmic granules. Potassium bichromate.
In adrenal medulla, The chromaffin reaction of the granules is due to their content of __________.
Catecholamines. Epi & NorEpi
Increases the heart rate and cardiac output without significantly increasing the BP and other metabolic effects.
Epinephrine
Is in the brain and peripheral tissues, the principal transmitter substance of adrenergic neurons.
Norepinephrine
Develops from the caudal part of the roof of the diencephalon. It appears as an epithelial thickening on the midline by the ____ of development. Then it invaginates to become a solid organ located at the roof of the _______.
Pineal gland. 7th week. Mesothelium.
Pineal gland is AKA
Epiphysis cerebri
The pineal gland is a slightly _________ shape appendage of the brain, attached to the roof of the ______ by the ______.
Flattened cone. 3rd ventricle. Peduncle.
The pineal gland is made up of pale staining ________, with _________ granular nuclei and prominent nucleoli, the _______.
Epitheloid cells. Round/oval. Pinealocytes.
In pineal gland, the second cell type is the _______, which occur in the perivascular areas. They are less numerous and nuclei are ______ & ______.
Interstitial cells. Darker & Smaller.
In pineal gland, this provide supporting network to the cells.
Neuroglial cells
In the pineal gland, these are mulberry shaped concretions largely of ________, which makes the radiological landmark.
Brain sand. Hydroxyapatite.
Other name for Brain sand
Corpora arenacea/Psammoma’s bodies
Pineal gland reaches its’ maximal development by the _________ and regresses later in life.
Middle of first decade
Pineal gland has a high level of ________ & ________.
Serotonin & Melatonin.
Serotonin & Melatonin are secreted by the
Pinealocytes
Controls the onset of puberty
Pineal gland
Has an exocrine & endocrine portion
Pancreas
Part of the pancreas which secretes hormones
Endocrine portion
Part of the pancreas which secretes digestive juice essential for the digestion of carbohydrates, fats & proteins.
Exocrine portion
The endocrine function of the pancreas is performed by a highly vascularized aggregation of secreting cells which are scattered all throughout. Comprised only one to two percent of the gland.
Islets of Langerhans
The islets of Langerhans develops from the _____________ during the ______ of development and scattered throughout the gland.
Parenchymatous pancreatic tissue. 3rd month.
Insulin secretion begins on the ____ of development.
5th month
The islets are _________ masses of _____ staining cells arranged in a form of _________ anastomosing cords, with a few fine connective tissue fibers.
Spheroidal. Pale. Irregular.
Islets of Langerhans are more abundant in the ________. The secretion is released into the _______ where it has access to the bloodstream. By special methods, there are _____ types distinguished.
Tail of pancreas. Interstitium. Six.
Principal Cells of the Islets of Langerhans
Beta cells, Alpha cells & Delta cells “BAD”
Secrete somatostatin
Delta cells
Secrete insulin
Beta cells
Secrete glucagon
Alpha cells
Alpha cells tend to be at the ______ of the islet.
Periphery.
Are the predominant type distributed throughout the islet, comprising 60% to 90% of its mass.
Beta cells
Are the least abundant occuring anywhere in the islet.
Delta cells
In Islet of Langerhans, The hormones secreted by the three principal types are involved in the control of level of
Blood glucose
When glucose levels rise too high, the _______ release ______, which lower it.
Beta cells. Insulin.
When the sugar falls below the optimal level, the ______ secrete ______, which raises blood sugar.
Alpha cells. Glucagon.
The ________ produced by the ________ is capable of suppressing the secretion of insulin and glucagon and modulate the activity of the Alpha & Beta cells to maintain normal glucose levels.
Somatostatin. Delta cells
Thick fibrous capsule of the testes
Tunica albuginea
Thin fibrous septa, ________, extend radially dividing the organ into compartments, the ________.
Septula testis. Lobuli testis.
Is a compound tubular gland enclosed in a thick fibrous capsule, the tunica albuginea.
Testes
In the testes, each lobule is composed of one to four _____________, which constitute to the ______ of the testis.
Convoluted seminiferous tubules. Exocrine.
Is an endocrine component of the testis. These are lovated in the interstices between the seminiferous tubules. The cells occur in various group sizes. Small blood vessels are usually present.
Leydig cells
Shape & size of the Leydig cells
Large and ovoid. Polygonal.
Nucleus of Leydig cells
Large eccentric nucleus
Cytoplasm of Leydig cells
Granular acidophilic cytoplasm.
Leydig cells are located where
Peripherally vacuolated
The Leydig cells synthesize
Testosterone
In the testes, the ultrastructure typifies that of ___________ which have extensive smooth endoplasmic reticula.
Steroid secreting cells
Peculiar to human, is a variable number of proteinaceous crystals,
Reinke’s crystals
Are slightly flattened, ovoid, paired organs suspended on either side of the uterus
Ovaries
Ovary has two zones
Medulla and Cortex
A broad outer zone of the ovaries
Cortex
A central deeper zone of the ovaries
Medulla
The cortex of the ovaries consists of a ______, ______ connective tissue in which are scattered the characteristic epithelial structures of the ovary, the _______ in different stages of growth and degeneration.
Compact. Cellular. Ovarian follicles.
As the follicles increase in size, the ______ differentiates into a highly vascular inner layer of secretory cells.
Theca folliculi
In ovaries, secretes estrogen
Theca interna
In ovaries, an outer layer that is composed mainly of connective tissue
Theca externa
Following ______, the follicular wall collapses and its’ ______ cell lining is thrown into folds. There is extravasation of blood from the capillaries of the theca interna, resulting in _______.
Ovulation. Granulosa cell. Central clot.
The theca interna and granulosa cells then enlarge and accumulate lipid and are transformed into plump, pale staining polygonal cells, the _________. These structure is now called ______.
Lutein cells. Corpus luteum.
Staining of Lutein cells
Pale staining
Shape of Lutein cells
Polygonal
The development of theca interna cells of the ovary is from the secondary cortical cords from the proliferation of cells in the
Stroma ovarii
In ovaries, Whar are the two kinds of Lutein cells
Granulosa Lutein cells & Theca Lutein cells
Size & Staining of Theca Lutein cells
Smaller and darker stained
Size of the Granulosa Lutein cells
Larger
Kind of Lutein cells which secrete progesterone
Granulosa Lutein cells
Kind of Lutein cells which secrete small amount of estrogen
Theca Lutein cells
Other organs with endocrine function
Placenta, Fat & Kidney “PFK”
In the placenta, the _______ of the chorionic villi secrete _________.
Syncitiotrophoblast. Human chorionic gonadortropic hormone (HCG)
Is a special type of connective tissue in which fat cells predominate.
Adipose tissue
Are found isolated in all loose connective tissue, but in certain places they are present in such large numbers and have such organization as to justify the designation of adipose tissue.
Fat cells
Adipose cells are _____, ____ or ____ shaped cells, whose cytoplasm is displaced to the _______ region of the cell by the presence of a single large fat droplet.
Large, oval or spherical. Peripheral.
The nucleus of adipose cells is ______ and surrounded by a small amount of cytoplasm in the _______ giving a characteristic “________” appearance.
Flattened. Periphery. Signet ring.
The principal functions of adipose tissue are
Storage of fat, Insulation against heat loss & Mechanical support im certain body regions “SIM”
Two types of adipose tissue
Brown adipose tissue & Yellow/White adipose tissue
Comprise the bulk of the body fat. It is an adult fat or mature form of adipose tissue from which ranges in color from white to dark yellow.
Yellow/White adipose tissue
This type of adipose tissue is a fetal fat or immature form of adipose tissue. Its’ color ranges from tan to reddish brown.
Brown adipose tissue
The adipose cell contains a single large fat droplet in the cytoplasm. It is unilocular as to morphology.
Yellow/White adipose tissue
This type is found in the subcutaneous tissue of skin, omentum, mesenteries and retroperitoneal fat.
Yellow/White adipose tissue
Its’ cell contains multiple lipid droplets in the cytoplasm; hence, it is multilocular in morphology.
Brown adipose tissue
Found in the intercapsular and inguinal regions of the newborn
Brown adipose tissue
On one side of the wall of the afferent arteriole at the vascular pole becomes transformed into modified smooth muscle cells called
Juxtaglomerular cells
Staining of the cytoplasm of JG cells. Their specific granules are clearly demonstrated.
Basophilic
In electron microscopy of secretory granules of JG cells shows that cells are variable in shape and membrane bounded with an __________ structure.
Internal crystalline
JG cells secrete
Renin
Activated by Renin will lead to
Conversion of Angiotensinogen into Angiotensin I
Potent vasoconstrictor, increasing BP.
Angiotensin II
Inactive but is converted in the lungs to A2
Angiotensin I
These cells are formed at one angle between the efferent and afferent arteriole at the vascular pole.
Lacis cells/Extraglomerular mesangial cells
Lacis cell produces
Erythropoietin
Other name for Mesangial/Lacis cells
Polar cushion/Polkissens cells
A hormone that stimulates erythropoiesis in the bone marrow
Erythropoietin
Hypersecretiom of GH during childhood
Gigantism
Hyposecretiom of GH by the adenohypophysis
Pituitary dwarfism
Hypersecretiom of GH during adulthood
Acromegaly
Hyposecretion of ADH caused by damage to the neurohypophysis or the supraoptic nucleus
Diabetes Insipidus
A heterogenous group of diseases, all of which lead to an elevation of blood sugar and excretion of glucose in the urine.
Diabetes Mellitus
Hyposecretion of thyroid hormones during growth years.
Cretinism
Two clinical manifestations of cretinism are
Dwarfism & Mental retardation
Hypothyroidism during adulthood. Hallmark of this disorder is an ______ that causes the facial tissues to swell and look puffy.
Myxedema. Edema.
Hyperthyroidism during adult life. This gives rise to __________.
Grave’s disease. Exopthalmic goiter.
Muscle twitches or spasm and convulsions as a result of hypoparathyroidism (deficiency in calcium)
Tetany
Hyperparathyroidism that causes demineralization of bone
Osteitis fibrosa cystica
Hypersecretion of the mineralocorticoid, aldosterone, characterized by a decrease in the body’s _______ secretion.
Aldosteronism. Potassium.
Primary adrenal insufficiency that results in hyposecretion of glucocorticoids. Clinical manifestations include lethargy, weight loss and hypoglycemia, which leads to muscular weakness.
Addison’s disease
Hypersecretion of glucocorticoids, especially cortisol and cortisone. Clinical manifestations include moon face, buffalo hump on the back and pendulous abdomen.
Cushing’s syndrome
Tumor of the chromaffin cells of the adrenal medulla, causes hypersecretion of the medullary hormones.m
Pheochromocytoma
