Endocrine System Flashcards
What is the endocrine system?
Released hormones into the bloodstream.
A hormone is a chemical messenger released by a gland that affects activity in another part of the body
What do hormones do?
Regulate body function
Growth and development
Sexual development and reproduction
What are the two types of hormones?
Circulating
Locally acting
What is a circulating hormone?
Hormones that enter the blood stream to access distant targets
What is a local hormone?
Hormones that act locally so do not enter the blood stream
How do hormones trigger cell receptors?
Hormones activate target cell and bind to the cell receptors. The responde is then triggered
What is the pituitary?
Inside the brain, below the hypothalamus
“Master gland”
Hormones control parts of the body and other endocrine glands
What hormones does the anterior pituitary secrete?
Growth hormone - growth and metabolism
Thyroid stimulating hormone - stimulates thyroid to produce hormones
FSH/LH - controls oestrus and ovulation
What hormones does the posterior pituitary secrete?
Oxytocin - uterine contractions and milk production
Anti-diuretic hormone (ADH) - controls water salt levels through vasoconstriction (causes the kidney to release less water)
What are the two adrenal glands?
Cortex and medulla
Located on top of each kidney
What hormones does the cortex secrete?
Aldosterone (maintains water balance by conserving sodium and releasing potassium)
Cortisone (increases blood glucose levels and slows nonessential functions during fight or flight)
What hormone does the medulla secrete?
Adrenaline (makes heart beat faster and lungs more efficient)
What hormones does the thyroid secrete?
Thyroxine (T4)
Triiodothyronine (T3)
Both regulate the metabolic rate
2-lobed gland in the neck
What hormones does the parathyroid secrete?
Parathyroid hormone (PTH) - maintains normal calcium and phosphorus levels
4 small glands
What hormones does the ovaries secrete?
Oestrogen
Progesterone
Controls oestrus (heat) and maintains pregnancy
