Summary of Active, Passive, and Bulk Cell Transport

Video Summary

The video discusses the mechanisms of cell transport through the Plasma Membrane, highlighting three primary types: Passive Transport, Active Transport, and Bulk Transport.

Plasma Membrane Functionality:
The Plasma Membrane is selectively permeable, regulating the passage of substances into and out of the cell.
Types of Transport:
- Passive Transport: Movement of substances without energy expenditure.
  - Diffusion: Movement from high to low concentration until equilibrium is reached.
  - Facilitated Diffusion: Faster Diffusion through specific channel or carrier proteins.
  - Osmosis: Diffusion of water, often aided by aquaporins.
- Active Transport: Requires energy (ATP) to move substances against their concentration gradient.
  - Example: Sodium-potassium pump, which exchanges sodium and potassium ions.
- Bulk Transport: Used for large molecules that cannot pass through transport proteins.
  - Endocytosis: Plasma Membrane engulfs particles to bring them into the cell.
    - Phagocytosis: Engulfing large particles (e.g., bacteria).
    - Pinocytosis: Engulfing liquids or small particles.
    - Receptor-Mediated Endocytosis: Specific uptake of molecules through receptor proteins.
  - Exocytosis: Release of substances from the cell via vesicles fusing with the Plasma Membrane.

Passive Transport:
- Diffusion
- Facilitated Diffusion
- Osmosis (via aquaporins)
Active Transport:
- Sodium-potassium pump mechanism
Bulk Transport:
- Endocytosis (phagocytosis, pinocytosis, receptor-mediated)
- Exocytosis