endocrine system Flashcards
The multiple activities of the cells, tissues, and organs of the body are coordinated by the inter-play of several types of chemical messenger systems.
COORDINATION OF BODY FUNCTIONS BY CHEMICAL MESSENGERS
These are released by axon terminals of
neurons into the synaptic junctions and act locally to control nerve cell functions
NEUROTRANSMITTERS
These are released by the glands or the
specialized cells into the circulating blood and influence the function of target cells into another location in the body.
ENDOCRINE HORMONES
These are secreted by neurons into the circulating blood and influence the function of target cells to another
location of the body.
NEUROENDOCRINE HORMONES
Are secreted by the cells to the extra-
cellular fluid and affect neighboring target cells at a different type
PARACRINES
Are secreted by cells into the extra-
cellular fluid and affect the function of the same cells that produce them
AUTOCRINES
These are peptides secreted by cells to
the extra-cellular fluid and can function as autocrine, paracrine, or endocrine hormones
cytokines
are secreted by helper cells and act on other cells in the immune system and they are under the cytokines
cytokines
are chemical substances that are secreted by endocrine cells into the extra-cellular fluids and regulate the metabolic activity of other cells in the body.
Hormones
It affects target organs found throughout the body
Hormones
these are hormones that are secreted by anterior and posterior pituitary gland. Th pancreas and parathyroid gland.
PROTEINS AND POLYPEPTIDES
the hormones secreted by adrenal cortex and the ovaries, testes, and placenta
STEROID
what organ produces proteins and polypeptides?
pancreas and parathyroid glands
what organ produces steroids?
Adrenal cortex, ovaries, testes and placenta
Secreted by the thyroid and adrenal medulla
Derivatives of tyrosine
what do you call polypeptides with 100 or more amino acids?
proteins
fewer amino acids are referred to as?
Peptides
are hormones that synthesizes on the rough end of the endoplasmic reticulum in the same fashion as other proteins
Protein and peptide hormones
an organelle that is stored within the cytoplasm and many our bound into the cell membrane until their secretion is needed
Vesicles
what hormones are increased when calcium ions are also increased?
cyclicAMP (Cyclic adenosine monophosphate)
a hormone that is usually synthesized from cholesterol and are not stored
steroid hormones
what chemical structure of steroid hormones are similar to?
Cholesterol
what hormones are lipid soluble that consist of three cyclohexyl rings and cyto pentyl rings?
Steroid hormones
describe the appearance of steroid hormones
chemical structure is same like the cholesterol and it has three cyclohexyl rings and cyto pentyl rings that are combined into a single structure
where are much of the cholesterol producing cells come from?
Plasma
are hormones derived from tyrosine
Amine
what are the two glands that produces the 2 groups of hormones derived from tyrosine?
Thyroid gland and adrenal medullary hormone
the two groups of hormones from the thyroid gland and adrenal medullary hormones are formed by the __________ and _________ of the _______ cells
enzymes and cytoplasmic compartments, glandular cells
is one of the characteristics of endocrine glands.
Feedback
prevents overactivity of hormone systems. After a stimulus causes a release of hormone conditions of products resulting from the action of hormone tends to suppress its further release.
negative feedback
it occurs when a biological action of the hormone causes additional secretion of the hormone
positive feedback
a variation that occurs in hormone release
Cyclical variations
a variation of hormone that are influenced by seasonal changes, various stages of development and aging or the daily cycle and sleep.
Periodic variations
What variation is the secretion of growth hormones?
Periodic variations
secretion of growth hormones occurs during?
sleeping time
are hormones that are dissolved in the plasma and transported from their sites of synthesis to target cells/tissues?
Water-soluble hormones
Circulate in the blood while being mainly bound to plasma proteins
Steroid and thyroid hormones
how many percent of steroid or thyroid hormones exist freely in the plasma?
less than 10% of the solution
cannot easily diffuse across the capillaries and gain access to their target cells and are therefore biologically inactive until they dissociate from plasma proteins
protein-bound hormones
what are the ways that hormones are cleared from the plasma?
➢ Metabolic destruction by the tissues
➢ Binding with the tissues
➢ Excretion by the liver into the bile
➢ Excretion by the kidneys into the urine
what membrane are specific mostly for the protein, peptide, and catecholamine
hormone
membrane receptors
membrane receptors are specific mostly for the ________ , ________ and ___________
protein, peptide and catecholamine hormone
they are the primary receptors for the different steroid hormones?
Cytoplasm
primary receptors for the different steroid hormones
cytoplasm
The receptors for thyroid hormones
nucleus
what hormones uses the mechanism of direct gene activation?
Steroid hormones and thyroid hormones
why are the steroid hormones and thyroid hormones are able to diffuse to the plasma membrane at their target cells?
because they are lipid soluble molecules
The most common stimulus, in which endocrine gland organs are prodded into action by other hormones
Hormonal stimulus
is the changing of blood levels of certain ions and neutrons
HUMURAL STIMULUS
humeral stimulus is also known as
humurol stimuli
are nerve fibers stimulate hormone release and the target cells respond to the neural stimuli
neural stimuli
what nervous system is an example of the neural stimuli?
Sympathetic nervous system
what organ stimulates the body during stress? and what organ is it?
Norepinephrine and epinephrine, adrenal medulla
what approx. size is the pituitary gland?
Size of a pea
Where is the pituitary located?
Located at the hypothalamus of the brain where it hangs from the stock of the inferior surface
the pituitary gland is surrounded by what bones?
sella turcica and sphenoid bone
what are the 2 functional lobes of the pituitary gland?
anterior pituitary (Adenohypophysis)
posterior pituitary (neurohypophysis)
other term of the anterior pituitary
adenohypophysis (pars distalis)
other term of posterior pituitary?
neurohypophysis (pars nervosa)
also known as the master gland? Why is it called the master gland?
Pituitary gland as it affects thyroid, adrenal cortex, ovary, mammary gland and pancreas
what are the 5 thyroid cell types?
- Somatotropes – hGH: Secretes
human growth Hormone - Corticotropes – ACTH: Secretes
Adrenocorticotropic hormone - Thyrotropes – TSH: Secretes Thyroid Stimulating Hormone
- Gonadotropes – LH, FSH:
Stimulates Luteinizing Hormone
and Follicle-stimulating hormone - Lactotropes – PRL: Secretes
prolactin
what are the metabolic effects of the growth hormones?
Promotes protein deposition
Enhances Fat Utilization
Decreases carbohydrate utilization
in what time of the day and night do growth hormones stimulate?
during the day and midnight, it also stimulates during strenuous exercises
whats the pattern of growth hormones when it is secreted?
Cyclical pattern
Decreased blood glucose. under what growth hormone effects is it? Stimulate or Inhibit?
stimulate growth hormone
aging. under what growth hormone effects is it? Stimulate or Inhibit?
inhibit growth hormones
obesity. under what growth hormone effects is it? Stimulate or Inhibit?
Inhibit growth hormone
starvation. under what growth hormone effects is it? Stimulate or Inhibit?
stimulate growth hormone
protein defiency. under what growth hormone effects is it? Stimulate or Inhibit?
Stimulating growth hormone
increased blood free fatty acids. under what growth hormone effects is it? Stimulate or Inhibit?
inhibit growth hormone secretion
is the decrease secretion of all the anterior pituitary hormones.
Panhypopituitarism
is the decrease function and production of glucocorticoids adrenal glands
Hypothyroidism
the decrease secretion of ________________ so that sexual functions are lost
gonadotropic hormones
results from generalized deficiency of anterior pituitary secretion or an effect of panhypopituitarism during childhood.
dwarfism
what is the posterior pituitary gland or neurohypophysis composed of?
Pituicytes (glial cells)
what does the pituicytes do?
supporting structure of the large numbers of terminal nerve fibers and terminal nerve endings from nerve tracks
from the pituicytes where does the terminal nerve endings and terminal nerve fibers originating from?
Supraoptic nucleus and paraventicular nucleus of the hypothalamus
what does the nerve endings that forms like a bovious knobs contains?
Secretory granules
what are the two posterior pituitary hormones namely?
vasopressin and oxytocin
other term of vasopressin
antidiuretic hormone
located immediately before the larynx and n each side of the anterior to the trachea
thyroid gland
what are the two major hormones produced by the thyroid gland?
thyroxin
triiodothyronine
it is one of the largest endocrine glands and weighs around __________
thyroid gland, 15-20 grams
what percentage do you consider when it is a lack of thyroid?
40-50% below normal
at what percent do you consider the thyroid to be excess?
60-100% above normal
what does the thyroid gland secretes?
Calcitonin
what are the two types of follicles that are found in the thyroid gland?
Follicles and parafollicular cells
what does the parafollicular cells secretes?
calcitonin
are colloid filled follicles surround by cuboidal follicular cells
follicles
how do you oxidizing the iodine?
through the use of hydrogen peroxide and peroxidase
1st step in making thyroid hormones
oxidation of the iodine
2nd step of the thyroid production
organification of the thyroglobulin
after the formation of the thyroid hormones where are they stored? and how many months are the thyroid good for?
in the follicles, 2-3 months
also known as the t4
thyroxin
also known as the T3
triiodithyronine
increased or enlargement of the thyroid gland. Whatever the causes: graves’ disease, tumor, adenomas, carcinomas
goiter
most common form of hyperthyroidism, an autoimmnue disease which antibodies of the thyroid stimulating immunoglobulins form against the TSH receptors
grave’s disease
is the protrusion of the eyeballs
exolphthalmus
almost total lack of thyroid hormone. what are its symptoms?
myxedema , bagginess of the eyes and swelling of the face
extreme hypothyroidism during fetal life. Failure of body growth and by mental retadation it results from congenital lack of thyroid gland
cretinism
how many are the parathyroid glands? and where are they located?
4 parathyroid glands, upper portion of the parathyroid gland one of each behind the upper and of each lower poles of the thyroid
is the complete removal of the parathyroid gland
thyroidectomy
what are the parathyroid gland cells made of?
chief cells and oxyphil cells
are cells that are not present in babies and animals?
oxyphil cells
believed to secrete most if not all of the parathyroid hormone(parahormone)
chief cells
oxyphil cells
modified or defeated chief cells that no longer secretes hormone
what hormone stimulate bone resorption causing the release of calcium into the extra cellular fluidat
parathyroid hormones
what hormone also increases reabsorption of calcium and decreases reabsorption of phosphate by the renal tubules leading to decreased excretion of calcium and increase excretion of phosphate
parathyroid hormone
how many adrenal glands does a human body have?
and where are they located?
2 right and left