Chapter 17 Endocrine Part 1 Flashcards
what system works together with the nervous system
endocrine
common goal of the endocrine system
achieve/ maintain homeostasis
the endocrine system consists of
endocrine glands/ tissue throughout the body
endocrine glands secrete what
chemical messengers
what are chemical messengers
hormones
the endocrine system transports throughout the body via
blood
the endocrine system binds to
receptors on target tissue
what events does the endocrine and hormones control
- growth and development
- tissue formation
- metabolism and energy balance
- reproduction
- sexual development
- fluid, electrolyte and nutrition homeostasis
- behavior
- immune system
hormones stimulate osteocytes to secrete new matrix, neurons form and strengthen synapses and skeletal muscle fibers enlarge
growth and development
hormones stimulate glucose regulation
production of enzymes essential for food breakdown/ absorption
adjusrs HR, BP, RR to better adapt to current metabolic demand
metabolism
hormones regulate renal function, controlling which ions/ water retained or excreted, regulate pH of plasma, # and types of blood cells produced and the amount of proteins in blood plasma
blood compositioin
hormones regulates reproductioin via production of gametes
also role in milk production/ let down in breast feeding
reproduction
electronic signaling
nervous sytem
nervous system has wired or wireless system
wired
wired system=
localized effect
the response in the nervous system is rapid and brief duration or slower and long lasting
rapid and brief duration
the nervous sytem reacts to far or close proximity
close
can some molecules act as both neurotransmitters and hormones depending on the source
yes
is the endocrine system electronic or chemical signaling
chemical
produced by neurons, secreted into synapse, travels short distance ro adjacent cell= effector
neurotransmitter
neuron, gland or muscle=
paracrine agents
examples of neurotransmitters
acetylcholine and epinephrine
cell produces a hormone that act on itself
autocrine
example of autocrine
t lymphocytes with an infection
cell produces hormone that acts on neighboring cells
paracrine
ductless, releases substance into the blood to a distant target cell
endocrine
hormones are produced and secreted by
endocrine glands
where do hormones travel
in the blood
at the target hormones stimulate a
response
hormone actions are usually
cell specifici
protein molecules bind specifically with hormones and trigger specific physiologic changes in target cell
receptor
chemical messengers created in response to
stimulation
hormones travel via blood to all
tissues in the body
can hormones turn things on or off when bind to receptor
yes stinulate or inhibit
hormones are regulated by what in the brain
hypothalamus
the action of a hormone at the target is established by
receptors on or in target organ cells
what is source tissue
where the hormone is released into the blood stream
what is a source tissue for insulin
pancreatic islet cells
what is target tissue
possesses receptors for the hormone and responds to the hormone by a specific action
major endocrine glands include
- pineal gland
- hypothalamus
- pituitary gland
- thyroid gland
- parathyroid gland
- thymus
- pancreas
- adrenal glands
- testicles or ovaries
- placenta during pregnancy
nontraditional hormone secreting organs
heart
kidneys
stomach
intestines
adipose tissue
what nontraditional hormone organ secretes atrial natruretic peptide
heart
what nontraditional hormone organ secretes erythropoietin
kidneys
what nontraditional hormone organ secretes renin
kidneys
what nontraditional hormone organ secretes gastrin
stomach
what nontraditional hormone organ secretes cytokines, incretins, ghrelin
intestines
what nontraditional hormone organ secretes leptin and adiponectin
adipose tissue
3 types of stimuli control hormone release
humoral, hormonal, neural
in humoral control, the production of hormone is controlled by the level of the controlled substance in the
blood flowing through the endocrine source tissue itself
example of humoral control
the control of glucose by insulin and glucagon production and release by the pancreas
in neural control, production of a hormone is controlled by the
direct neural stimulation of the source tissue
the only occurance of the neural control is
direct sympathetic stimulation of the adrenal medulla to release catecholamines directly into the blood stream
in hormonal control, production of a hormone is controlled by the
blood level of a hormone produced by a different source tissue
hormones stimulate secretion of other hormones are called
tropic hormones
tropic means
endocrine to endocrine
most common tropic hormones is
anterior pituitary
inhibitory hormones are released from hypothalamus and
prevent tropic hormone release
also negative feedback=
no stimulus which decrease TH release
3 patterns to determine hormone blood levels
chronic
acute
episodic
constant blood levels over long timeframe
chronic
when hormone concentration sudden/ irregular changes short timeframe, circulating levels differ with each stimulus
acute
when hormone secreted at predictable intervals and concentrations, predictable bursts
episodic
fluctuate during month (cyclical)
reproductive hormones
can polar hormones pass through cell membrane
no
can polar hormones get through mucosa of gut
no
how do polar hormones need to be adminstered
by injection
how do polar hormoned act outside cell
act as second-messenger mechanisms
examples of polar hormones
catecolamines, melatonin, calcitonin
polar means
water soluble
lipophilic hormones include
steroid and thyroid hormones
can lipophilic hormones cross cell membrane
yes
how are lipophilic hormones adminstered
orally
most common controlling mechanism
negative feedback
hormones secretion is inhibited by
hormone itself
what senses that something is wrong
hypothalamus
pituitary hormone travels via
bloodstream
pituitary hormone travels via the bloodsteam to target organ to produce
new hormone
target organ hormone is produced which signals the
hypothalamus
hypothalamus senses balance and
stops signaling the pituitary
what is a rare mechanism
positive feedback
what does positive feedback do
acceletates original process
positive feedback continues until
certain action is complete
