What method of transport is required when molecules must be moved against the concentration gradient? A. diffusion
B. Active transport
C. facilitated diffusion

b. active transport

Explanation:

active transport moves molecules from a lower concentration to a higher concentration against the concentration gradient with the use of energy

hope this helps

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d