Question: what is the difference between the medulla and cortex?
Answer: The adrenal cortex (being a cortex) is the outermost layer of the adrenal gland while the adrenal medulla (being a medulla) is the middle or inner layer of the adrenal gland. The former (as an outer layer) surrounds the entire medulla. The second difference between the two is the hormones that they secrete or release.