The definitions
- Osmosis: students forget "through a partially permeable membrane." Required: net movement of water molecules from a dilute solution to a more concentrated solution through a partially permeable membrane.
- Diffusion: students say "movement" instead of "net movement." Required: net movement of particles from higher to lower concentration.
- Active transport: students forget "requires energy from respiration." Required: movement against the concentration gradient, using energy from respiration.
- Excretion: confused with egestion. Required: removal of metabolic waste products (not undigested food).
- Enzyme: students say "speeds up reactions." Required: biological catalyst that increases the rate of a specific reaction without being used up.
- Respiration: confused with breathing. Required: chemical reactions in cells that release energy from glucose (not "breathing" or "gas exchange").
- Photosynthesis: students miss "light energy." Required: process by which plants use light energy to convert CO₂ and water into glucose and O₂.
- Homeostasis: students say "keeping things the same." Required: maintaining a constant internal environment.
- Denaturation: students say the enzyme is "destroyed." Required: the active site changes shape (permanently) so the substrate can no longer fit.
- Gene: students say "carries traits." Required: a section of DNA that codes for a specific protein.
How to learn them
Write each definition as a checklist of required elements. Cover the checklist, write the definition from memory, then check. The elements you missed are what you need to practise. Repeat every few days until you consistently include all elements.