Zusammenfassung der Ressource
Biology: Transport Across Cell Membranes
- Diffusion
- The closer to the gas = the higher the concentration
- Oxygen and Glucose go into the cell, Carbon Dioxide comes out the cell
- Not all materials can diffuse
- The higher concentration moves to the lower concentration
- This like a ball rolling down a hill, no energy is required
- This is called passive transport
- Osmosis
- Diffusion with water
- The more water a plant absorbs, the heavier the plant is
- Is required to get through selectively permeable membranes
- A membrane that can decide what goes through and what doesn't
- Osmosis moves from high water concentration to low water concentration
- This is like a ball rolling down a hill, no energy is required
- This is called passive transport
- In plants, if too much water is absorbed, it will make the vacoule expand
- This is known as a turgid cell
- In animals, if there is too little water, the cell will shrivel up
- It does not burst as plant cells have a cell wall
- In plants, if there is not enough water, it will shrivel up
- Thi is known as a plasmolysed cell
- In animals, if there is too much water, the cell will burst!
- Active transport
- This is when the low concentration moves to the high concentration
- Like a ball. It can't go uphill so you will have to push it. This requires energy