endocrinology 1 Flashcards
What are endocrine glands?
organs or groups of ells which synthesise and secrete hormones and pass them directly into blood
Do endocrine glands have ducts?
no
Name an exocrine gland?
salivary glands
What organ has exocrine and endocrine function?
pancreas
Is the hypothalamus a gland or cell?
cluster of neurones
Is the anterior pituitary a gland or cells?
gland
Is the posterior pituitary gland or cells?
extension of the hypothalamic neurones
What is a hormone?
chemical secreted from an endocrine gland (or cell) and travels in the blood to its target organ and mediates a specific effect
What are 3 types of hormones?
steroid
peptide
amine
Can prolonged activity of hormones be harmful?
yes, tight regulation is important - limitation of hormones is key
What happens as glucose levels increase?
insulin increase too
What happens if the insulin effects are not switched off/limited?
(unchecked insulin activity)
go into hypoglycaemic state
loss of nervous system function
What organs degrade blood hormone?
liver/kidney enzymes
How do hormones leave the body?
urine/bile
What is the balance of hormones regulated by?
half-life
time needed for conc to half
What re ways hormones are prodiuced?
1) chronic/constitutive
i.e. maintains constant conc in the blood
2) acute/stimulated
i.e. episodic release when required
3) cyclic/pulsatile
i.e. shows regular rhythm of release
What hormone is produced chronic/constitutively?
thyroid hormone
What hormone is released acute/stimulated?
insulin
What hormones are released cyclic/pulsatile?
growth hormone
linked to pineal gland - melatonin
What does the peak in cyclic/pulsatile hormones correlate to?
physiologically relevant times
e.g. growth development