Distinguish between active and passive transport. Active Transport- the movement of from an area of low concentration to an area of high concentration that require the cell to use energy. Explain how the sodium potassium pump operates. Sodium Potassium Pump- works to maintain a higher concentration of Na+ outside the cell and a higher concentration of K+ inside the cell. 3 Na+ ions bind to a carrier protein inside the cytosol. A phosphate from ATP binds to protein changing it shape. The 3 Na+ ions are released into the external environment. 2 K+ ions bind to the carrier protein. The phosphate group is released causing the protein to change shape. The K+ ions are released into the cytosol. At top speed, the pump can transport about 450 Na+ ions and 300K+ ions per second. This exchange of ions creates an electrical gradient across the membrane. Compare and contrast endocytosis and exocytosis. Endocytosis the process of ingesting macromolecules or large particles. The particles are enveloped by a cell membrane forming a pouch called a vesicle. The vesicles go on to fuse with other membrane bound organelles. pinocytosis- the transport of solutes or fluids phagocytosis- the movement of large particles or whole cells Exocytosis- when vesicles in the cytoplasm fuse with the cell membrane to release its contents into the cell’s external environment.
Distinguish between active and passive transport. Active Transport- the movement of from an area of low concentration to an area of high concentration that require the cell to use energy. Explain how the sodium potassium pump operates. Sodium Potassium Pump- works to maintain a higher concentration of Na+ outside the cell and a higher concentration of K+ inside the cell. 3 Na+ ions bind to a carrier protein inside the cytosol. A phosphate from ATP binds to protein changing it shape. The 3 Na+ ions are released into the external environment. 2 K+ ions bind to the carrier protein. The phosphate group is released causing the protein to change shape. The K+ ions are released into the cytosol. At top speed, the pump can transport about 450 Na+ ions and 300K+ ions per second. This exchange of ions creates an electrical gradient across the membrane. Compare and contrast endocytosis and exocytosis. Endocytosis the process of ingesting macromolecules or large particles. The particles are enveloped by a cell membrane forming a pouch called a vesicle. The vesicles go on to fuse with other membrane bound organelles. pinocytosis- the transport of solutes or fluids phagocytosis- the movement of large particles or whole cells Exocytosis- when vesicles in the cytoplasm fuse with the cell membrane to release its contents into the cell’s external environment.