29. Compare and contrast endocytosis and exocytosis. 30. Compare and contrast pinocytosis and phagocytosis.

29. Endocytosis and exocytosis are two processes that cells use to transport materials in and out of the cell. Endocytosis is the process by which cells take in materials from the outside by engulfing them in a vesicle. This process requires energy and is used to take in large molecules or particles that cannot pass through the cell membrane. Exocytosis, on the other hand, is the process by which cells expel materials from the inside to the outside by releasing them in a vesicle. This process also requires energy and is used to release large molecules or particles that have been synthesized or stored within the cell.<br /><br />30. Pinocytosis and phagocytosis are two types of endocytosis. Pinocytosis, also known as "cell drinking," is the process by which cells take in small particles or fluids from the outside by engulfing them in a vesicle. This process does not require energy and is used to take in small molecules or particles that can pass through the cell membrane. Phagocytosis, on the other hand, is the process by which cells take in large particles or cells from the outside by engulfing them in a vesicle. This process requires energy and is used to take in large molecules or particles that cannot pass through the cell membrane. Phagocytosis is often used by immune cells to destroy pathogens or debris.