Which of the following examples is a specific case of active transport?
A) A carrier proteins moves sucrose across the membrane with the concentration gradient.
B) cytoplasmic Na+ mines to the sodium potassium pump, ATP is used, and NA+ is released to the outside.
C) water moves from an area of high free-water concentration to an area of low free-water concentration.
D) Aquaporins facilitate the diffusion of water in the red blood cells of mammals.
Answer: B) cytoplasmic Na+ mines to the sodium potassium pump, ATP is used, and NA+ is released to the outside.