Within the National 5 Biology course, you will need to know:
- The cell membrane consists of phospholipids and proteins and is selectively permeable.
- Passive transport occurs down a concentration gradient and does not require energy. Examples of passive transport are diffusion and osmosis.
- Diffusion is the movement of molecules down a concentration gradient from a higher to a lower concentration.
- Osmosis is the movement of water molecules from a higher water concentration to a lower water concentration through a selectively permeable membrane.
- Animal cells can burst or shrink and plant cells can become turgid or plasmolysed. Relationship between different concentrations of solutions and their effect on cells.
- Active transport requires energy for membrane proteins to move molecules and ions against the concentration gradient.
The following links offer some useful revision on Transport Across Cell Membranes to support your learning:
BBC Bitesize – Transport Across Cell Membranes
BBC Bitesize Video – Transport Across Cell Membranes
To help with your learning, you may also wish to try some of the following resources:
