Describe the main types of endocytosis and how they differ

The three main types of endocytosis are phagocytosis, pinocytosis, and receptor-mediated endocytosis. These differ based on the size, type of material taken in, and how specific the process is-

• Phagocytosis ("cell eating") – The cell engulfs large solid particles, such as bacteria or cell debris.
• Pinocytosis ("cell drinking") – The cell takes in fluids and dissolved substances in a non-specific way.
• Receptor-mediated endocytosis – A selective process where the cell uses surface receptors to bind and internalize specific molecules.