B11 - Hormonal Coordination Flashcards
Define hormones.
chemicals scrtd by glands & trnsprtd -> target organs in bldstrm
Where is the pituitary gland found? What is its function?
brain - ‘master gland’ scrts several hmns into bld
Where is the thyroid gland found? What is its function?
base of neck - scrts thyroxine = cntrls metabolic rate of body
Where is the pancreas found? What is its function?
by kidneys - scrts insulin or glucagon -> cntrl glucose lvls in body
Where are the adrenal glands found? What is its function?
above kidneys - scrts adrenaline for ‘fight or flight’ response
What is the function of the ovaries?
produces oestrogen
What is the function of the testes?
produces testosterone
What are the 3 main differences between the endocrine system and the nervous system?
ECS - long lived response, slow response, uses chemical messages
NVS - short response, rapid response, uses elctrcl impulses,
Define glucagon.
hormone ↑ bld glcs lvls
Define insulin.
hormone ↓ bld glcs lvls
What is glucose?
sgr
Define glycogen.
str molecule for glcs
What is a negative feedback loop?
systm that tries to mntn stdy state
What happens if blood glucose levels increase?
pancreas releases insulin
After the pancreas releases insulin, what happens in the body?
glcs moves from bld -> mscl cells & liver
insulin stimulates liver to turn excess glcs
-> glycogen = bld glcs lvls normal
What happens in blood glucose levels fall?
pancrease releases glucagon
After the pancreas releases glucagon, what happens in the body?
glucgn stmlts liver turn glycogen -> glucose
What causes Type 1 diabetes?
pancreas does not produce insulin
What causes Type 2 diabetes?
body stops responding to insulin
What are risk factors of Type 2 diabetes?
genetics, age, obesity & lck of exercise
How can Type 1 diabetes be managed?
insulin injections
How can Type 2 diabetes be managed?
diet (eg.carbohydrate intake) & exercise
How can Type 1 diabetes be cured?
pancreas trnsplnts
How can Type 2 diabetes be cured?
it can’t be cured
Define a negative feedback loop.
system that tries to maintain steady state
What does thyroxine do? Where is it made?
stimlts basal metabolic rate - thyroid
What does thyroxine play an important role?
grwth & dvlpmnt
Define basal metabolic rate.
metabolic rate when ur body is @ rest
Define metabolism.
sum of all reactions in body
The levels of which 3 hormones are controlled negative feedback?
insulin, glucagon & thyroxine
What are the levels of thyroxine controlled by?
TSH (thyroid stimulating hormone)
Where is TSH made?
pituitary
What happens if there is a fall in thyroxine in the blood?
- pttry gland releases more TSH
- trggrs thyroid gland -> release more thyrxn
- normal thyrxn levels
What happens if there is a rise in thyroxine in the blood?
- pttry gland prvntd from releasing TSH
- trggrs thyroid -> release less thyroxine
- normal thyrxn levels
What are the effects of adrenaline on the body?
↑ heart rate = more oxygen & glucose are dlvrd -> brain & muscles
preprng body for ‘fight or flight’
Define secondary sexual characteristics.
changes that occur when u go thrgh puberty
How long does the menstrual cycle last?
28 days
What is oestrogen’s role in the menstrual cycle?
thickens uterus lining
stops release of FSH & stimulates release of LH
On day 1 of the menstrual cycle, what happens? What is this process called?
egg & uterus lining are lost in a period = menustration
On day 7 of the menstrual cycle, what happens?
uterus wall thickens & new egg matures in ovary
On day 14 of the menstrual cycle, what happens?
egg is released & uterus wall is @ thickest
What is it called when the egg is released?
ovulation
On day 21 of the menstrual cycle, what happens?
egg moves down fallopian tube & if egg is unfertilised = lining breaks down
What is FSH’s role in the mentstrual cycle?
causes egg -> grow & mature & stimulates ovaries to produce oestrogen
What is LH’s role in the menstrual cycle?
stimulates release of egg
What is progesterone’s role in the menstrual cycle?
maintains uterus lining & stops release of FSH & LH
Why is it important for the changes to the uterus to occur?
so zygote (fertilised egg) can implant itself in uterus lining
Where is FSH & LH secreted?
pttry gland
What is the main male reproductive hormone? Where is produced? What it’s function?
testes - testosterone -> stimulate sperm prdctn
In the first stage of the menstrual cycle, what hormone is produced?
FSH released by pttry gland
After FSH had been intially released, what happens?
FSH trvls in blood -> ovaries where it causes egg -> mature
At the same time of FSH causing an egg to mature, what happens?
FSH stmlts ovaries -> release oestrogen
What does oestrogen do once it has been released from the ovaries?
stops pttry glands releasing FSH & stmlts it -> release LH
Once the pttry gland has started releasing LH, what happens?
ovary releases egg & ovaries produce progesterone
After the ovaries starts producing progesterone, what happens?
progesterone stop pttry gland from releasing FSH & LH
Why would progesterone levels fall?
if fertilisation does not take place
