Master GCSE Biology

MS1:

- Photosynthesis is the process by which plants use sunlight, carbon dioxide, and water to make glucose (1)

MS2:

- Chlorophyll absorbs light energy from the sun (1)

- This energy is used to split water molecules to release oxygen (1)

MS3:

- Light intensity: Lower light intensity reduces the rate of photosynthesis (1)

- Carbon dioxide concentration: Lower CO2 concentration limits the availability of substrate (1)

- Temperature: Extremes of temperature can denature enzymes involved in photosynthesis (1)

MS4:

MS5:

- Aerobic respiration uses oxygen to break down glucose completely (1)

- This produces 36-38 ATP molecules per glucose molecule (1)

- Anaerobic respiration does not use oxygen and produces only 2 ATP molecules per glucose molecule (1)

MS6:

- Fermentation is an anaerobic process that breaks down glucose in the absence of oxygen (1)

- It produces lactic acid in animals and ethanol in plants (1)

- It releases a small amount of energy, 2 ATP molecules per glucose molecule (1)

MS7:

- Oxygen debt is the amount of oxygen needed to restore the body to its normal level after strenuous exercise (1)

MS8:

- Higher intensity exercise results in a higher oxygen debt (1)

- This is because anaerobic respiration is used more intensively at higher intensities (1)

MS9:

- Enzymes speed up biochemical reactions without being consumed (1)

- They lower the activation energy required for reactions (1)

- They are specific to particular reactions and substrates (1)

- They can be denatured by changes in pH, temperature, or substrate concentration (1)

MS10:

- Glucose is the main energy source for cells (1)