autocrine
liver regeneraion and t cells
regulates own cells
paracrine
regulates adjacent cells
endocrine
acts on distant cells, like adrenaline
classes of hormones
steriods: go straight in,
peptides: acth, oxytocin,
a. a:
adrenal medulla
produces adrenaline and noradrenaline
adrenal cortex
3 layers: g, f, r
outer layer aldesterone