Which of the following correctly identifies active transport?
(1 point)
Transport proteins move large molecules from areas of low concentration to areas of high concentration using cellular energy.
Transport proteins move large molecules from areas of low concentration to areas of high concentration without the use of cellular energy.
Small molecules move from areas of high concentration to areas of low concentration using cellular energy to enter a cell.
Small molecules move from areas of low concentration to areas of high concentration without using cellular energy to enter a cell.
http://www.google.com/#q=active+transport+molecules
The correct identification of active transport is option (1):
Transport proteins move large molecules from areas of low concentration to areas of high concentration using cellular energy.
To arrive at this answer, we need to understand the process of active transport. Active transport is a type of cellular transport that requires the use of energy to move substances across the cell membrane against their concentration gradient (from areas of low concentration to areas of high concentration). This process is carried out by specific transport proteins embedded in the cell membrane.
Option (2) is incorrect because active transport indeed requires cellular energy.
Option (3) is incorrect because the movement of small molecules from areas of high concentration to areas of low concentration is known as passive transport, not active transport.
Option (4) is also incorrect because active transport involves moving substances from areas of low concentration to areas of high concentration, thus requiring cellular energy.
Therefore, the correct answer is option (1).