Endocrine system Flashcards
endocrine system,
made up of a number of secretory glands
gland
organ that makes chemicals and releases them out of the gland
endocrine gland 2
ductless
secretes hormones directly into the bloodstrean
what are hormones
chemical messengers
what are hormones secreted by
endocrine glands
how are hormones transported
carried in the blood to the target area
what do hormones cause
a response in the target area (long-lasting effect)
most hormones are composed of what?
protein
exocrine gland 2
ducted glands
have tubes to carry secretions away
3 exocrine glands
salivary, sweat and mammary
pancreas
both an endocrine and exocrine gland
endocrine action in pancreas
production of enzymes in pancreatic juice for digestion
exocrine action in pancreas
production of insulin and glucagon
6 hormones secreted by the pituitary gland
FSH LH Oxytocin prolactin TSH ADH
function of FSH
stimulates agg and sperm formation
function of LH
stimulates ovulation in female
function of oxytocin
stimulates contraction in uterus during birth
function of prolactin
stimulates milk production
function of TSH
stimulates thyroid gland to secrete thyroxine
function of ADH
stimulates reabsorption of H2O in the kidney
6 hormones secreted by the pituitary gland
FSH LH Oxytocin prolactin TSH ADH
function of FSH
stimulates agg and sperm formation
function of LH
stimulates ovulation in female
function of oxytocin
stimulates contraction in uterus during birth
function of prolactin
stimulates milk production
function of TSH
stimulates thyroid gland to secrete thyroxine
function of ADH
stimulates reabsorption of H2O in the kidney
what does the thyroid secrete?
thyroxine
function of thyroxine 2
controls metabolic rate
stimulates growth and development in children
endocrine part of pancreas
islets of Langerhans
what does the pancreas secrete
insulin
function of insulin 2
lowers blood sugar
stimulates formation of glycogen in the liver
what secretes adrenaline
adrenals
function of adrenaline 2
fight/flight response
raises blood sugar and heart rate
2 secretions of ovary
oestrogen and progesterone
function of oestrogen 2
development of female sexual characteristics
repair and growth of lining of womb
function of progesterone
growth and maturation of lining of womb
what do the testis secrete
testosterone
function of testosterone 2
development of male sexual characteristics
formation of sperm in males
what does the thyroid gland consist of
2 lobes in front of the trachea in the throat
what does the thyroid produce
the hormone thyroxine
what does thyroxine consist of
protein and iodine
what controls the release of thyroxine into the blood stream
TSH
TSH
thyroid stimulating hormone
what secretes TSH
the pituitary gland
2 functions of thyroxine
to control the rate of metabolism
to control growth and development in young children
when is thyroxine really important
during growth in young children
2 disorders of the thyroid gland
deficiency of thyroxine
excess of thyroxine
deficiency of thyroxine
underachieve thyroid
deficiency of thyroxine in children
cretinism
2 symptoms of cretinism
physical and mental development is retarded
corrective measures of cretinism
take thyroxine tablets
deficiency of thyroxine in adults leads to
myxoedema
3 symptoms of myxoedema
tiredness, depression, weight gain
corrective measure of myxoedema
take thyroxine tablets
when too much thyroxine is produces
Grave’s disease
3 symptoms of Grave’s disease
swollen neck, high metabolic rate, weight loss
2 corrective measures of Grave’s disease
remove part of the thyroid by surgery
kill some thyroid cells using radioactive therapy
control of thyroxine is by
feedback mechanism
feedback mechanism
where the production of a hormone stimulates or inhibits the production of itself or another hormone
positive feedback
stimulates production
negative feedback
inhibits production
when the level of thyroxine in the blood is below the required level
the pituitary gland secretes TSH (positive feedback)
when the level of thyroxine in the blood is above the required level
it inhibits the pituitary gland from secreting TSH (negative feedback)
response of nerve
fast acting
response of hormone
slow acting
length of response of nerve
short lived
length of response of hormone
long lived
transmission of nerve
electrical
transmission of hormone
chemical
speed of transmission of nerve
rapid
speed of transmission of hormone
slow (in blood)
effect of nerve
one area
effect of hormone
may affect many areas (target organs)
5 hormone supplements
insulin contraception HRT fertility treatment anabolic steroids
what is insulin used for
to treat diabetes
what secretes insulin
pancreas (cells of Langerhans)
3 functions of insulin
lowers the blood sugar level
stimulates conversion of glucose to glycogen in the liver
stimulates all cells in body to take up glucose
3 symptoms of diabetes
high blood sugar
kidneys excrete glucose in urine
weight loss
2 ways to control diabetes
regular injections of insulin a short time before meals
controlled intake of carbs (small amount at short intervals)
contraception
prevents egg formation and is used by many women to prevent a pregnancy
HRT
oestrogen used in the menopause
what does oestrogen do/?
stimulates bone formation and prevents osteoporosis
fertility treatment
hormones similar to FSH used in IVF to stimulate egg production
anabolic steroids
synthetic forms of male sex hormone testosterone
what are anabolic steroids used for
to promote muscle growth and bone strength
3 side effects of anabolic steroids
damage to kidneys, liver and heart
shrunken testes and enlarged breasts in males
development of male traits in females
