Endocrine Glands Flashcards
Secretory product of endocrine cells and organs that passes into the circulatory system (bloodstream) for transport to target cells.
Hormones
The hormone is secreted from one cell and acts on adjacent cell that expressed the specific receptors.
Paracrine
A cell that may produce molecules that act on themselves or on cells of the same type
Autocrine
A signaling molecule that remains on the secreting cell’s surface or adjacent extracellular matrix and affects target cells when the cells make contact.
Juxtacrine
A type of hormone that is particularly important in embryonic and regenerative tissue interactions.
Juxtacrine
These are often also target organs for other hormones that can establish a feedback mechanism to control hormone secretion and keep blood hormonal levels within strict limits.
Endocrine glands
Lies below the brain in a small cavity on the sphenoid bone, the sella turcica (saddle)
Pituirary gland (hypophysis)
The pituitary gland (hypophysis) is formed in the embryo partly from the developing _________ and partly from the developing _________.
Brain and oral cavity respectively
Retains many histologic features of brain tissue
neurohypophysis
Secretory cells in which hormone is stored in cytoplasmic granules.
Chromophils
These stain weakly, with few or no secretory granules, and also represent a heterogeneous group including stem and undifferentiated progenitor cells as well as any degranulated cells present.
Chromophobes
growth hormone
somatotrophs
prolactin
lactotrophs
adrenocorticotrophic hormone
corticotrophs
Follicle-stimulating hormone and luteinizing hormone
gonadotrophs
thyroid stimulating hormone
thyrotrophs
smaller funnel-shaped region surrounding the infundibulum of the neurohypophysis
pars tuberalis
Refers to most of the cells of the pars tuberalis
gonadotrophs
Thin zone of basophilic cells between the pars distalis and the pars nervosa of the neurohypophysis
pars intermedia
Storage site for neurosecretions
Posterior pituitary
Pituicytes resemble __________
astrocytes
most abundant cell type in the posterior pituitary
pituicytes
frequent urination
polyuria
increased thirst
polydipsia
Stimulates contraction of uterine smooth muscle during childbith and the myoepithelial cells in the mammary gland.
Oxytocin
Regulates pituitary gland activity
hypothalamus
An increase in one of the stimulating hormone would trigger an increase of the effector gland hormone
positive loop
An increase in the level of the effector gland hormone would suppress the release of the stimulating hormone
negative feedback loop
Regulates the daily rhythms of bodily activities
pineal gland/epiphysis cerebri
chief cells of the pineal gland
pinealocytes
Calcified concretions of the pinealocytes
corpora arenacea/brain sand
These cells produce melatonin
Pinealocytes
half-moon shaped flattened structure
adrenal gland
This affects carbohydrate metabolism and can also induce fat mobilization and muscle proteolysis
Cortisol
A highly vascular, butterfly-shaped gland
thyroid
Help control the basal metabolic rate in cells throughout the body
thyroid hormones thyroxine and tri-iodothyronine
Excessive growth of thyroid follicles and enlargement of the thyroid gland
goiter
The only endocrine gland in which a large quantity of secretory product is stored
thyroid
principal cells responsible for the production of the thyroid hormones T4 and T3
follicular cells
An important regulator of blood calcium levels
parathyroid hormone
secrete primarily glucagon
A cells
produce insulin
B cells
secrete somatostatin
D cells
secrete pancreatic polypeptide
PP cells
Plays a role in regulating motility and secretions of all types within the digestive system
diffuse neuroendocrine system
