Active Transport in Cells - Moving objects into and out of the Cell

A water pump uses energy to push water uphill or against gravity. In the same way a cell has different methods to move molecules against their natural flow and into and out of the cell. Welcome to MooMooMath and Science and Active Transport. In order to stay alive cells need to move objects in and out of the cell. However, sometimes these objects are either too large or need to go against the concentration gradient. Active transport comes to the rescue. However, active transport requires energy in the form of ATP to move these objects in and out. Let's take a look at three types of active transport. Membrane pumps, endocytosis, and exocytosis. A membrane pump moves substances against the concentration gradient or from a low concentration to a high concentration. A good example is the sodium potassium pump. Three sodium ions attach to the carrier protein. ATP attaches a phosphate to the carrier protein and it changes its shape. This allows three sodium ions to leave the cell and then two potassium ions now attach to the carrier protein. The phosphate detaches from the protein and it changes shape once again and the potassium now travels into the cell. This allows sodium and potassium to go against the concentration gradient. The cell also uses two types of vesicle movement, endocytosis and exocytosis. Endocytosis allows the cell to move larger objects into the cell by engulfing the object and then moving this object into the cell. There are three types of endocytosis. Phagocytosis, which is when a cell moves in solids. Penocytosis, which is when a cell moves in liquids. And receptor mediated endocytosis, which is a form of endocytosis in which receptor proteins on the cell surface capture a specific target molecule. When the receptors bind to their endocytosis is triggered and the receptors and their attached molecules are taken into the cell in a vesicle. Exocytosis occurs when the cell expels an object out of the cell. Objects inside the cell are encased in a vesicle which is expelled. If you'd like to know more about active transport this playlist will help. And as always thanks for watching and MooMooMath uploads a new math and science video every day.