ENDOCRINE SYSTEM Flashcards
the organs of the endocrine system produce ________________ called __________, which are involved in the regulation of other orgasn
chemical signals, hormones
endocrine system works closely with the ________________ to maintain ___________
nervous system, homeostasis
comparison of the nervous system and endocrine system (time of respond)
nervous system- faster to respond
endocrine system- response is slower
comparison of the nervous system and endocrine system ( action time)
nervous system - action lasts for short time
endocrine system- action last longer
comparison of the nervous system and endocrine system (targets)
nervous system- specific targets
endocrine system- multiple targets
comparison of the nervous system and endocrine system (involved)
nervous system- neurotransmitters are involved
endocrine system- hormones are involved
what hormones does hypothalamus produces
ADH, oxytocin and regulatory hormones
what hormones does pituitary gland produces
anterior lobe: ACT, TSH, GH, PRL
posterior lobe: release of ADH and oxytocin
what hormones does thyroid gland produces
Thyroxine, triiodothyronine, calcitonin
what hormones does adrenal gland produces?
adrenal medulla: epinephrine , norepinephrine
adrenal cortex: cortisol, corticosterone, aldosterone, androgens
what hormones does pancreas produces?
insulin
glucagon
what hormones does pineal gland produces
melatonin
what hormones does parathyroid glands produces
parathyroid hormone
organs with secondary endocrine functions
- heart
- thymus
- adipose tissue
- digestive tract
- kidneys
- gonads ( testes and ovaries)
kidneys secrets
- erythropoietin hormones
- calcitriol
adipose tissue secretes
leptin
hormones are ______ _______. hormones are a means of
chemical signals , hormones are a means of communication between cells, between body parts and even between individual
hormones affect the _______ of cells that have _________________
metabolism, receptors to bind them
________ link between the nervous and endocrine systems is referred to as a ________________ organ
hypothalamus , neuroendocrine organ
function of hypothalamus
control body temperature and water-salt balance
control the secretions of the pituitary gland
what are the two portions of pituitary gland called
posterior and anterior pituitary
thyroid-stimulating hormone
stimulates the thyroid to make thyroid hormones
adrenocorticotropic hormone
stimulates the adrenal cortex to produce cortisol
gonadotropic hormones such as
follicle-stimulating hormone and luteinizing hormone
follicle-stimulating hormone and luteinizing hormone
stimulates the gonads to produce gametes and sex hormones
prolactin
produced only after childbirth and causes the mammary glands to produce milk
what are the different types of physiologic effects of thyroid hormones
- calorigenic effect
- growth
- development
- cardiovascular system
- central nervous system
- reproductive system
too little growth hormone in children
pituitary dwarfism
too much growth hormone in children
gigantism
too much growth hormone in adults
acromegaly
pancreas secretes
insulin and glucogen
neurosecretory cells in the hypothalamus produce the hormones __________ and ____________.
antidiuretic hormone and oxytocin
When blood is too concentrated, ________ is released from the posterior pituitary
antidiuretic hormone
how does ADH dilute the blood,
when blood is concentrated, ADH is released from the posterior pituitary. ADH causes more water to be reabsorbed into kidney capillaries. As blood become dilute, ADH is no longer released.
function of oxytocin
causes uterine contractions during childbirth and milk letdown during breastfeeding
what is the illness that unable to produce ADH
diabetes insipidus
what is diabetes insipidus 1
it is the inability to produce ADH. Produce large amounts of urine, resulting in severe dehydration and loss of important ions. Can be corrected with administering ADH
A normal levels of thyroid hormone are essential to the development of _________ and ______________
fetal and neonatal brain
how does thyroid hormones affect the cardiovascular system?
Thyroid hormones increases heart rate, cardiac contractility and cardiac output. They also promote vasolidation (widening of blood vessels) , which leads to enhance blood flow to many organs
how does thyroid hormones affect the central nervous system?
both decreased and increased concentrations of thyroid hormones lead to alterations in mental state. Too little thyroid hormone, and the individual tends to feel mentally sluggish, while too much induces anxiety and nervousness.
how does thyroid hormones affect the reproductive system?
normal reproductive behaviour and physiology are dependent on having essentially normal levels of thyroid hormone.
___________ is commonly associated with infertility .
hypothyroidism
what is exophthalmic goiter
over secretion of thyroid hormone. thyroid is overactive and enlargers forming a goiter. Eyes protrude from edema in eye socket tissue.
symptoms of exophthalmic goiter?
hyperactivity, nervousness, irritability
treatment for exophthalmic goiter
surgical removal or destruction of a portion of the thyroid by radioactive iodine
cogenital hypothyroidism is also known as
cretinism
what is congenital hypothyroidism
underdeveloped thyroid at birth which leads to under secretion of thyroid hormone
what happens if thyroid hormone therapy is begun in the first 2 months of life
the baby will experience intellectual disability results
what is myxedema
hypothroidisim in adults
symptoms of myxedema
hypothyroidism in adults
symptoms of myxedema
lethargy, weight gain, loss of hair, slower pulse, cold intolerance, lowered body temperature
when is calcitonin secreterd
when blood calcium levels rise
What happens if calcitonin is secreted ?
brings about the deposition of calcium into the bones, and reduces the activity and number of osteoclasts. when blood calcium levels lower to normal, the release of calcitonin is inhibited
Parathyroid hormone is produced by the
parathyroid glands
when is parathyroid hormones released?
in response to low blood calcium levels.
what happens if parathyroid hormone is secreted
?
promotes the activity of osteoclasts, which remove calcium from the bones. activates vitamin D (calcitrol), which promotes calcium reabsorption by the kidneys and stimulates absorption of calcium ions from food. These effects bring the blood calcium level back to the normal range, and PTH secretion stops.
what is hypoparathyroidism?
insufficient PTH production. causes a dramatic drop in blood calcium, followed by excessive nerve excitability. Increased nerve signals cause tetany- continuous muscle contraction. Without treatment, causes seizures, heart failure, and death.
what is hyperparathyroidism
over secretion of PTH.
hyperparathyroidism
over secretion of PTH. can result in osteoporosis because of continuous calcium release from the bones. may also cause kidney stones.
adrenal glands consists of
adrenal medulla and an outer cortex
describe the response of the adrenal medulla to stress
the hypothalamus sends signals that travel through preganglionic sympathetic nerve fibers to the adrenal medulla to stimulate it to secrete its hormones. epinephrine (adrenaline) and norepinephrine (noradrenaline) bring about changes that occur during a fight-or-flight response, a short term response to stress.
major types of hormones produced by the adrenal cortex
- glucocorticoids
- mineralcorticoids
adrenal cortex also secretes a small amount of _________
male and female sex hormones
glucocorticoids secretion is controlled by
ACTH (adrenocorticotropic hormone)
examples of glucocorticoids
cortisol, corticosterone and cortisone
functions of glucocorticoids
regulate carbohydrate, protein, and fat metabolism
raise the blood glucose level
active in stress response and the repair of damaged tissues
relieve swelling and pain from inflammation.
functions of mineralocorticoids
regulate ion balance in the body
renin-angiotensin-aldosterone system
describe how mineralocorticoids regulate blood pressure in the body
mineralcorticoids targets the kidney, where it promotes absorption of Na+ and excretion of K+.
Renin secreted by the kidneys when blood Na+ levels and blood pressure are low.
Renin converts angiotensinogen to angiotensin 1. Angiotensin 1
androgens
male sex hormones
estrogen
female sex hormones
estradiol
a form of estrogen
the primary androgen is _________________ which is a precursor for ______________.
dehydroepiandrosterone, testosteron
what is an addison disease ?
hyposecretion of glucocorticoids
without glucocorticoids, __________ cannot be replenished in a stressful situation.
glucose
what is a cushing syndrome ?
over secretion of glucocorticoids
Excess glucocorticoids cause
muscle protein to be broken down and fat to be deposited in the midsection
steroidal medications are used as
anti-inflammatory drugs to treat medical conditions such as asthma, multiple sclerosis.
exocrine tissue of pancreas is called
pancreatic islets
exocrine tissue of pancreas secretes
digestive enzymes
alpha cells of pancreas secretes
glucagon
beta cells of pancreas secretes
insulin
delta cells of pancreas
somatostatin
delta cells of pancreas regulate
the digestive processes
is pancreas under pituitary control or no
no, pancreas responds directly to changes in blood glucose levels
when is insulin secreted
secreted when blood glucose levels are high (after eating)
insulin stimulates the
uptake of glucose by cells, especially liver cells, muscle cells and adipose tissue.
Glucagon is secreted when
blood glucose levels are low
glucagon stimulate the liver to
break down glycogen to glucose
glucagon promotes the use of
fat and protein in preference to glucose as energy sources
adipose cells break down ______ to ______ and______
fat, glycerol and fatty acids
liver take _______ and ______ and uses them toe make glucose
fatty acids and glycerol
significance of insulin
insulin is the only hormone in the body that decreases the blood sugar levels.
diabetes mellitus is due to either
hyposecretion of insulin or decreased sensitivity of insulin receptors
symptoms of diabetes mellitus
hyperglycemia glycosuria polyuria polyphagia polydipsia fatigue and weight loss
hyperglycemia
excess glucose in the blood
glycosuria
glucose is excreted in the urine
polyuria
diabetic urinate frequently
polydipsia
drinks a lot of water as feels thirsty always
gonads
the male testes and female ovaries
where is thymus located at?
beneath the sternum
thymosis causes ______ to mature
lymphocytes
pineal gland is located in the?
brain
the function of pineal gland
produces melatonin, primarily at night.
regulates the daily sleep-wake cycle. we get sleepy at night when melatonin levels increase and awaken once daylight returns and melatonin levels are low
regulates sexual development
function of erythropoietin
secreted by the kidneys in response to a low oxygen blood level
function of leptin
acts on hypothalamus; it signals satiety (fullness). obese people may have plenty, but it may be defective or they may not have enough receptors
leptins are produced by
adipose tissue
prostaglandins are made from
arachidonate, a fatty acid
the function of prostaglandins in the uterus
cause muscles to contract
cramps
the function of prostaglandins on the stomach
reduce gastric secretion, so treat gastric reflux
prostaglandins inhibit_______ ________ so prevent
platelet aggregation, thrombosis
prostaglandins lowers ________ so treat __________
blood pressure, hypertension
_______ is the most important os the mineralocorticoids
aldosterone
function of mineralocorticoids
regulate ion balances in the body
where are minerolocorticoids primary produced?
zona glomerulosa
is the secretion of mineralocorticoids controlled by the anterior pituitary?
no
what are the function of aldosterone
aldosterone primarily targets the kidney, where it promotes renal absorption of sodium ions and renal excretion of potassium ions
what happens during renin-angiotensin-aldosterone system
when the blood sodium level and pressure are low, the kidneys secrete renin. renin is an enzyme that converts the plama protein angiotensinogen to angiotensin I. angiotensin I is changed to angiotensin II by converting enzyme found in lung capillaries. angiotensin II stimulates the adrenal cortex to release aldosterone
what is reabsorption
water enters kidney capillaries and thus the blood.
a low blood calcium level stimulates the release of
PTH (parathyroid hromone)
what is the function of PTH
causes blood calcium level to increase
activates vitamin D
what happens when there is a low blood calcium level
low blood calcium level stimulates the release of PTH, which promotes the activity of osteoclasts and the release of calcium from bones
hypoparathyroidism causes a ________ in _______ followed by excessive _____________
nerve excitability
oversecretion of PTH can result in
osteoporosis because of calcium release from the bones
hormones produced by adrenal medulla
epinephrine (adrenaline) and norepinephrine (noradrenaline)
A cells of pancreas are responsible for the
secretion of hormone glucagon,
B cells of pancreas are responsible for
secretion of insulin
D cells of pancreas are responsible for the release of
somatostatin
what is somatostatin
hormone that is released at the same time as insulin to regulate the digestive processess
effect of insulin on human body
- uptake of glucose by cells
- increased synthesis of fat
- increased secretion of digestive enzymes
glucocorticoids regulate
carbohydrate, protein and fat metabolism
when blood sodium levels and bp are low , the kidneys secrete ________ which leads to the release of _____- from the adrenal cortex
renin ,aldosterone
explain how glucocorticoids raise the blood glucose level
- they promote the breakdown of muscle proteins to amino acids , taken up by the liver from the bloodstream. the liver then converts these excess amino acids to glucose, which enters the bloodstream.
- they promote the metabolism of fatty acids rather than carbohydrates and this spares glucose
chemical signals that influence the behaviour of other individuals are called
pheromones
