Master GCSE Biology

MS1:

- Tissue: A group of similar cells working together to perform a specific function (1)

- Example: Muscle tissue (1)

MS2:

- To increase the surface area for absorption (1)

- So more nutrients can be absorbed from food (1)

- To increase the rate of absorption (1)

MS3:

- Structure:

- Thin, elongated cell with a large surface area (1)

- Large central vacuole (1)

- Cytoplasm lining the cell membrane (1)

- Adaptations:

- Thin cell membrane allows water and ions to pass through by osmosis/diffusion (1)

- Large surface area increases the rate of absorption (1)

- Large central vacuole creates a low water potential inside the cell, drawing water and ions in (1)

MS4:

- Ribosome (1)

MS5:

- Active site has a specific shape (1)

- Substrate has a complementary shape (1)

- Active site and substrate fit together like a lock and key (1)

MS6:

- Bile emulsifies fats (1)

- Breaks large fat droplets into smaller ones (1)

- Increasing the surface area for lipase to work (1)

MS7:

- Artery (1)

MS8:

- Arteries have thicker, more muscular walls (1)

- They contract to push blood out of the heart (1)

- Veins have thinner, less muscular walls (1)

- They allow blood to flow back to the heart by gravity (1)

MS9:

- Role of valves:

- Prevent backflow of blood (1)

- Maintain pressure gradient in the heart (1)

- How valves ensure one-way flow:

- Flaps of tissue that open and close in response to blood flow (1)

- Blood pressure pushes the flaps open allowing blood to flow (1)

- When blood pressure drops, the flaps close to prevent backflow (1)

MS10:

- Transpiration (1)