endocrine system Flashcards
what is the endocrine system?
Is a chemical communication system operating via the bloodstream, which secretes hormones in order to regulate bodily function.
A system that co ordinates biological activity by secreting hormones into the blood stream from glands.
What do hormones do?
Are chemicals that circulate in the bloodstream to target sites throughout the body influencing many processes such as mood.
* Only respond to specific cell receptors known as target cells
* When enough hormones are stimulated this causes a reaction
what does the hypothalamus do ?
- links nervous to the endocrine system - maintains homeostasis of bodily systems.
- ES is regulated by the hypothalamus, which signals a target gland to increase levels of a hormone.
- When sufficient levels are met it shuts down.
What is the pituitary gland?
- Main function is to influence the release of hormones from other glands therefore regulates many of the body functions.
- ‘Master gland’ that produces
What hormones does the pituitary gland release?
ACTH
LH / FSH
oxytocin
What does ACTH do?
signalling hormone when we experience stress ( signals adrenal gand to produce cortisol)
LH / FSH → impor
where do the adrenal glands sit?
On top of the kidneys
what are the two structures that make up the adrenal glands?
Adrenal cortex (outer)
Adrenal medulla (inner)
What does the adrenal cortex release ?
Cortisol
Aldosterone
What does cortisol do?
important in cardiovascular functioning → it is increased in response to stress
What does aldosterone do?
responsible for maintaining blood volume and blood pressure
What does the adrenal medulla release? (2)
- noradrenaline
- adrenaline
What does adrenaline do?
vital for the fight or flight response. It causes physiological changes
What does noradrenaline do?
constricts blood vessels –> increasing blood pressure
what do the ovaries release?
progesterone and oestrogen
