Which of the following is a characteristic of active transport?
A. Saturable uptake rate.
B. Use of ATP or a proton gradient as a source of metabolic energy.
C. Can move materials against a concentration gradient.
D. All of the choices.
Answer: D
Which of the following is a characteristic of active transport?
A. Saturable uptake rate.
B. Use of ATP or a proton gradient as a source of metabolic energy.
C. Can move materials against a concentration gradient.
D. All of the choices.
Answer: D