Endocrine System Flashcards
what are tropic hormones?
target other endocrine glands and stimulate their growth and secretion
what are sex hormones?
they target reproductive tissue
what are anabolic hormones?
stimulate anabolism within their target cells.
what are steroids?
steroids are composed of cholesterol and diffuse easily through cell membrane
( ex. cortisol, estrogen, testosterone )
what are nonsteroids?
composed of amino acids and consists of proteins
( ex. insulin, oxytocin, adh )
what is synergism reaction?
when several hormones work together to create a greater effect than one by itself
what is permissiveness reaction?
when a small amount of one hormone
allows for the full effect of another
what is antagonism reaction?
one hormone produces the opposite effect
of another
how does steroid hormone action work?
form a hormone-receptor complex inside cells, and moves it to the nucleus to direct mRNA production, leading to transcription and translation. this process takes time, resulting in a delayed response.
how does nonsteroid hormone action work?
binds to receptors on plasma membrane, acting as messengers. this triggers a second messenger inside the cell, intimates a cascade of reactions, resulting in a quicker response compared to steroid hormones.
what are prostaglandins (PG)?
tissue hormones, influencing neighboring cells and are secreted by various orgas such as the kidneys, lungs, brain.
what does PGA do?
lowers blood pressure and increases blood flow
what is PGE?
regulates vascular effects, deformability, and hydrochloric acid production
what is PGF?
includes uterine contractions and aids normal peristalsis.
where is the hypothalamus located?
inferior side of brain and connected to pituitary gland.
what does the hypothalamus do?
acts as body’s thermostat, controls homeostasis, producing hormones that regulate heart rate, body temperature, hunger, and the sleep-wake cycle.
where is the pituitary gland?
connected to the hypothalamus by the
infundibulum, is composed of two glands.
what are the two glands in the pituitary gland?
the adenohypophysis (anterior pituitary) and the neurohypophysis (posterior pituitary)
what hormones does the adenohypophysis produce?
Growth Hormone (GH), Prolaction (PRL), and Tropin.
what hormones does neurohypophysis produce?
antidiuretic hormone (ADH) and Oxytocin
what is growth hormone (GH)
promotes growth and fat metabolism
prolactin hormone
supports breast milk development/production
what are the 4 types of tropic hormone includes?
TSH, ACTH, FSH, and LH
what does thyrotropin (TSH) do?
stimulates thyroid.
what does adrenocorticotropin (ACTH) do?
stimulates adrenal gland.
what does follicle stimulating hormone (FSH) do?
stimulates follicles and produces estrogen in
females and in males, stimulates the development of the seminiferous tubules and promotes spermatogenesis.
what does luteinizing hormone (LH) do?
stimulates the corpus luteum of the ovary. causes the secretion of estrogen and progesterone AND secretion of testosterone in males.
where is the pineal gland located?
found in the diencephalon
what does the pineal gland do?
involved in regulating biological clock by secreting melatonin
where is the thyroid gland located?
in neck, below larynx.
what does the thyroid gland do?
secrets calcitonin, which helps regulate calcium levels AND produces T3 and T4
what are the two hormones found in thyroid?
T4 and T3
what does T3 and T4 do?
regulate metabolism and cell growth.
what does the parathyroid gland do?
produces PTH (parathyroid hormone) which maintains calcium homeostasis by acting on bones.
where are the adrenal glands located?
above kidneys
what are the three zones of the adrenal gland?
Outer zone: mineralocorticoids
Middle zone: glucocorticoids
Inner zone: androgens
what is the mineralocorticoids purpose?
(e.g. aldosterone) adjusts blood pressure and volume
what is the glucocorticoids purpose?
(e.g. cortisol) regulates metabolism and respond to stress.
what is the androgens purpose?
influences secondary sexual characteristics and libido.
what hormones are cause “fight or flight”?
epinephrine and norepinephrine
what does the pancreas glands do?
produces insulin and glucagon which control the amount of glucose in the blood.
what does glucagon do?
release of glucose into blood when sugar levels are low
what does insulin do?
causes the reuptake of sugar by cells when glucose levels are high.
what are the gonads glands overall job?
produces sex hormones and gametes, plays critical role in reproductive development.
what hormones do females produce in the gonads?
estrogen, progesterone and
small amounts of testosterone.
what hormones do males produce in the gonads?
testosterone and small amounts of estrogen.
where is the thymus gland located?
above heart; medial to the lungs
what is the thymus glands purpose?
the maturation of T-cells and shrinks with age.
