All cell needs to be supplied with nutrients, electrolytes, water, and also all unwanted materials must be removed, and this can only be achieved by transport of substance in and out of the cell.
Active transport is the movement of a substance against the electrochemical gradient. For active transport to take place, energy is required. There are two major types of active transport which include:
Primary active transport which is a type of transport in which energy is released directly from the breakdown of ATP.
Secondary active transport is the transport of substance with the sodium ion. There are other special types of active transport, which include endocytosis, which is a transport mechanism in which macromolecules enter the cell, exocytosis is the process in which substance leaves the cell, and transcytosis is the process in which substance enter from one side of the cell.