SSC MTS EXAM

Detailed explanation-1: -Primary active transport directly uses a source of chemical energy (e.g., ATP) to move molecules across a membrane against their gradient.

Detailed explanation-2: -The active transport of small molecules or ions across a cell membrane is generally carried out by transport proteins that are found in the membrane. Larger molecules such as starch can also be actively transported across the cell membrane by processes called endocytosis and exocytosis.

Detailed explanation-3: -Active transport needs energy because it is not a passive transport and the molecules have to move against the concentration gradient. Hence it requires energy to be carried by the carrier protein. It requires the use of energy in the form of ATP.