water soluble hormones
- amino acid based hormones
- act on specific receptors located in the plasma membrane which then triggers response by the cell
- unable to cross plasma membrane
lipid soluble hormones
- steroid hormones
- able to cross plasma membrane and enter cell
- acts on receptors located inside the cell to trigger response by cell
humoral stimulus
- changing levels of a substance within the blood
neural stimulus
- nerves stimulate the release of hormones by gland
hormonal stimulus
- hormones released from one gland trigger another gland to release hormones
anterior pituitary lobe
- glandular tissue
- makes and secretes numerous hormones
posterior pituitary lobe
- nervous tissue
- stores hormones made by hypothalamus
- does not make any hormones
posterior pituitary- childbirth
- stimulated by stretching of cervix by babys head
- target: uterus
- action: contractions for childbirth
posterior pituitary- breast feeding
- stimulated by suckling on nipple
- target: mammary glands
- action: milk ejection
posterior pituitary- dehydration
- stimulated by increase in blood solute concentrations, decrease in blood volume and blood pressure
- target: kidneys
- action: increase water reabsorption back into blood
anterior pituitary- growth hormone
- target: muscles, bones, body tissues
- action: promotes growth
anterior pituitary- ACTH
- target: adrenal cortex
- action: secrete cortisol
anterior pituitary- luteinising hormone
- target: ovaries and testes
- action: ovaries- ovulation, estrogen&progesterone
testes- testosterone production
anterior pituitary- follicle stimulating hormone
- target: ovaries and testes
- action: egg and sperm production
thyroid gland
- iodine required in diet
- action: regulated basal metabolic rate, normal tissue growth and development
parathyroid gland
stimulus: low blood calcium levels
adrenal medulla - adrenaline
epinephrine- adrenaline
norepinephrine- noradrenaline
adrenal medulla
- increased heart rate
- vasoconstriction causing inc BP
- bronchioles dilate
- liver deposits glucose into blood
- diverts blood flow to key organs
excessive cortisol (from prolonged stress)
- stimulates elevated blood glucose
- anti-inflammatory effects
- suppression of immune system
- muscle wasting
- prolonged wound healing
pancreas
- secretes enzymes for food digestion
- release of hormones for regulation of blood and glucose levels
- alpha cells:glucagon
- beta cells: insulin
