Endocrine System Flashcards
an organ /tissue which contains specific receptor sites to a particular hormone
Target organ or tissue
Binding of hormone molecules to surface receptors on cell, triggers a __________ on target organ
preprogrammed response
secrete hormone into the bloodstream
glandular cells or glandular epithelium
Hormone comes from a Greek word “hormao” meaning?
to set into motion
What are the 4 General effects of Hormones
- Changes in plasma electrical permeability or electrical state
- synthesis of proteins or regulatory molecules
- activation and inactivation of enzymes
- stimulation of mitosis
steroidal hormones are formed from?
cholesterol
Receptors of the steroidal hormones are in the? non-steroidal?
nucleus; plasma membrane
steroidal hormones ______ through plasma membrane of target cell
diffuses
What is formed when steroidal hormones binds to the receptor protein?
hormone-receptor complex
What is the product of steroidal hormones?
new proteins
Non-steroidal hormones are _______
amino-acid based and are water soluble
receptor of the non-steroidal hormones are located on the target cells _____
plasma membrane
what is the second messenger of the non-steroidal hormone
cAMP or cyclic adenosine monophosphate
glands secrete their hormones in direct response to changing levels of ions or nutrients in the blood
humoral regulation
glands secrete their hormones when directly stimulated by the nervous system
neural regulation
glands secrete their hormones in response to hormones released by other endocrine glands
hormonal regulation
oxytocin is regulated via this feedback mechanism
positive feedback
deficient supply of the hormone
hyposecretion
excessive supply of the hormone
hypersecretion
Is hypothalamus a gland or not?
NOT
What are the five releasing hormones of hypothalamus?
TRH, CRH, GnRH, GHRH, PRH
lies in the sella turcica of the sphenoid bone at the base of the brain
pituitary gland
pituitary gland is also called as
hypophysis
a stalk-like structure that attaches the pituitary gland to the hypothalamus
infundibulum
blood vessels w/in the infundibulum that connect the capillaries of the hypothalamus to the capillaries of the anterior pituitary gland
hypophyseal portal veins
specialized form of nerve cells that secrete a “neurotransmitter” into the bloodstream rather than into a synaptic cleft; found in the hypothalamus & some may extend to the posterior pituitary
neurosecretory cells
posterior pituitary gland contains the __________ of neurosecretory cells whose cell bodies are in the hypothalamus
axons and axon terminals
TRUE OR FALSE: Posterior pituitary gland synthesize hormones.
FALSE
plays a role in childbirth & lactation
oxytocin
what is the target tissue of oxytocin?
smooth muscles in the walls of uterus
what is the stimulus of the oxytocin?
pressure on cervix
Growth hormone is also called as
somatotropin
what are the target organs of somatotropin?
liver, adipose tissue, muscles, bones, cartilage
how do growth hormone affect the blood glucose level?
it breaks down the adipose or fat for energy thereby increasing the glucose synthesis and blood glucose level
what is the effect of growth hormone to the muscles, bone and cartilage?
it increases the mitosis, amino acids transport and protein synthesis
occurs when there is excessive production of growth hormone after puberty
acromegaly
What is the stimulus of melanocytes-stimulating hormone?
excess corticotropin releasing hormone from the hypothalamus
what is the target cell of MSH?
melanocyte
What is the response of MSH?
skin darkening which occurs in hyposecretion of adrenal cortex
promotes lactation
prolactin
what is the response of prolactin?
milk production
Thyroid-stimulating hormone is also called as
thyrotropin
what is the stimulus of TSH?
TRH from hypothalamus
what are the thyroid hormones?
T3, T4, calcitonin
also called corticotropin
adrenocorticotropic hormone
What is the target organ of ACTH?
adrenal cortex
what is the stimulus of FSH?
GnRH or gonadotropin releasing hormone
what are the target organs of FSH?
testicles, follicles of ovaries
Secretion of estrogen
follicle stimulating hormone
Luteinizing hormone is also called ______ in males
interstitial cells stimulating hormone
what are the target organ of LH?
interstitial cells of testicles and follicles of ovaries
secretion of progesterone
luteinizing hormone
release of mature egg cells
ovulation
secretion of testosterone
LH or luteinizing hormone
hormone is released into the circulation and distribution to _________
distant organs and tissues
