8 - Endocrine System Flashcards
endocrine system is
a regulatory system
what are hormones
chemical messengers
where are hormones carried
in blood
Endocrine system works with __________ system to maintain ________
nervous
homeostasis
what secretes hormones
endocrine glands
hormones are carried in blood to what
target organs
endocrine glands do not have ______ but exocrine glands do
ducts
what do target organs have that allow hormones to act
receptors
3 ways hormones signalled to be released
nerve impulses
stimulating hormone
feedback loop
how do nerve impulses release hormone
nerve impulse is sent to signal a release of hormone is needed
how does stimulating hormone release hormones with example
a specific hormone released into blood to signal other endocrine gland to release hormone e.g. signal sent to thyroid to release thyroxin
how does feedback loop release hormone
level of substance in the blood directly controls release of hormone
feedback loop example
thyroid gland have parathyroid gland which maintains calcium levels so when low will start to release more
main list of endocrine glands (7)
pituitary
thyroid
parathyroid
adrenal
pancreas
ovaries
testes
gastrin secreted by
stomach
secretin secreted by
small intestine
chorionic gonadotropin secreted by
placenta
erythroprotein secreted by
kidneys
chorionic gonadotropin function
used to detect pregnancy
pituitary gland location
ventral to hypothalamus
pituitary gland function
secrete hormone that control other endocrine glands
pituitary gland process from hypothalamus to target organ
hypothalamus releases releasing hormone (xRH) to pituitary
pituitary gland releases stimulating hormone (xSH) to endocrine
endocrine gland releases hormone (x) to target organ
anterior pituitary produces (6)
TSH
ACTH
FSH
LH
GH
P
TSH
Thyroid stimulating hormone
tsh releases what
thyroxin
ACTH
Adrenocorticotropic hormone
ACTH releases what
cortisol
FSH
follicle-stimulating hormone
fsh does what
stimulates follicles to grow
LH
luteinising hormone
lh does what
reproduction
GH
growth hormone
gh does what
helps growth - stimulates lengthening of bones at growth plates
P
prolactin
prolactin does what
stimulates lactation
posterior pituitary produces (2)
antidiuretic hormone (ADH)
oxytocin
oxytocin functions (3)
milk let down
contractions of uterine muscles
bonding hormone between mum and offspring
adh function
acts in kidney to reduce water loss in urine - causes small amount of concentrated urine so water is kept in body
what is diabetes insipidus
deficient in adh so don’t produce concentrated urine
increased thirst and urine production
how to test for diabetes insipidus
dipstick in urine to check how concentrated - will be very weak and mainly water
thyroid glands location
either side of trachea
thyroid glands release (2)
thyroid hormones
calcitonin
thyroid hormones (2)
thyroxine (T4)
tri-iodothyronine (T3)
which is active and which is reservoir out of T3 and T4
T3 is active form
T4 is reservoir form
T4 is _______ into _____ once inside _____
converted
T3
cell
T3 function
controls metabolic rate - increases functions of body such as heart rate and cellular rate of energy use
thyroid hormone release process
thyrotropin-releasing hormone (TRH) from hypothalamus STIMULATES thyroid-stimulating hormone (TSH) from anterior pituitary
TSH stimulates thyroid glands to release thyroid hormones
how is thyroid hormone release negative feedback
when blood concentrations of thyroid hormones increase they inhibit both TSH and TRH
hypothyroidism is
too little T3/T4
hypothyroidism common in and rare in
common in dog and rare in cat
hypothyroidism clinical signs (5)
lethargy
weight gain
slow heart rate
alopecia
cold intolerance
hyperthyroidism is
too much T3/T4
hyperthyroidism common in
cats
hyperthyroidism clinical signs
weight loss
polyphagia (eating alot)
tachycardia
polyuria and polydipsia
diarrhoea…
parathyroid gland location
at top and bottom of each thyroid gland
parathyroid glands secrete
parathormone (PTH)
which hormone increases calcium
parathormone (PTH) from parathyroid
pancreas location
intestine
islets of langerhans location
pancreas
islets of langerhans secrete (2)
insulin and glucagon
insulin function
secreted in response to high blood glucose levels to decrease levels
glucagon function
secreted in response to low blood glucose to increase levels
diabetes mellitus is
increased blood glucose levels
diabetes mellitus are _______ and _______ to insulin
deficient and resistant
diabetes mellitus clinical signs
polyuria
polydipsia
weight loss
adrenal glands number
two
adrenal gland location
cranial end of each kidney
two parts of adrenal gland
adrenal cortex
adrenal medulla
adrenal medulla produces which hormones (2)
adrenaline
noradrenaline
adrenal medulla produces adrenaline which aids in
fight or flight
adrenaline has what affects on body
increase heart rate
dilation of airway
raise blood glucose
adrenal medulla releases adrenaline through which system
sympathetic nervous system
adrenal cortex releases which main hormone
cortisol
what is cortisol associated with
stress
what does cortisol do
increase blood glucose, speed and strength of heart
process of cortisol release
hypothalamus produces the corticotropin-releasing hormone (CRH)
CRH stimulates release of adrenocorticotropic hormone (ACTH) from pituitary
ACTH stimulates release of cortisol from adrenal cortex
adrenal cortex also produces ______ as well as cortisol
aldosterone
aldosterone function
acts in kidney to retain sodium and increases loss of potassium
purpose of retaining sodium and losing potassium
helps maintain correct blood volume and pressure
Addison’s disease is known as
hypoadrenocorticism
addisons disease is underactive or overactive
underactive - decrease production of cortisol
addisons disease clinical signs
lethargy
weakness
inappetence
cushing’s disease is known as
hypercortisolism
cushings disease is overactive or underactive
overactive - increased production of cortisol
cushings disease clinical signs
pot bellied appearance
calcium deposits
tumours in pituitary or adrenal glands
PUPD
lethargy
skin changes
high blood pressure
when sexually mature where does ova develop
follicles
after ovulation follicles become
corpus luteum
oestrogen location
developing follicle
progesterone location
corpus luteum
hypothalamus produces _________
gonadotropin-releasing hormone (GnRH)
GnRH stimulates _______
anterior pituitary
Anterior pituitary produces (2)
follicle stimulating hormone
luteinising hormone
FSH stimulates
oestrogen
LH stimulates
progesterone
oestrogen function
prepare body for mating
progesterone function
prepares body for pregnancy
at sexual maturity what secretes testosterone
leydig cells
