claim the interaction of motrin and robitussin can cause heart attacks in children
Active transport. Active transport is the movement of molecules across a cell membrane from a region of their lower concentration to a region of their higher concentrationâin the direction against some gradient or other obstructing factor (often a concentration gradient).
Sometimes diffusion is too slow or cell need to take or get rid of substances against a concentration gradient. Cells achieve this task by a special process called active transport. Active transport is the movement of substance across the cell membrane against a concentration gradient. Unlike the osmosis, active transport needs a great deal of energy, which has to be obtained from ATP. Active transport is achieved with the help of carrier protein in the plasma membrane. Usually the ions like Na+, Cl- and K+, and the molecules like glucose, amino acids, and vitamins are transported by active transport. For example, plants absorb mineral ions by using active transport.