Biology

• Diffusion


  The movement of molecules from an area of high concentration to an area of low concentration
• Diffusion


  • Occurs down a concentration gradient
  • Molecules move from high to low concentration
• Enzymes

  Biological catalysts that speed up chemical reactions
• Enzymes

  • Have an active site
  • Are highly specific
• Mitosis


  1. Cell division to produce new cells

  2. All cells have the same genetic material
• Stem cells can differentiate into specialised cells
• Blood cells are produced in the bone marrow
• The liver produces bile
• Nutrients in the digestive system are absorbed into the bloodstream
• Specialisation allows cells to perform specific functions
• Aerobic respiration uses oxygen to convert glucose into water and carbon dioxide, releasing energy
• Anaerobic respiration occurs without oxygen and produces lactic acid
• Metabolism is the sum of chemical reactions in a cell or organism
• Natural selection is the process by which organisms with favourable variations are more likely to survive and reproduce
• Variation is the differences between individuals in a species, controlled by genes
• Adaptation is a characteristic that increases an organism's chance of survival and reproduction
• Biodiversity is the variety of plant and animal species in a particular area
• Habitat


  The place where an animal or plant lives
• Community


  A group of different species living together in the same area
• Ecosystem


  A community of living organisms and their physical environment
• Ecology is the study of ecosystems
• Competition occurs when members of a community need the same limited resource
• Food chain


  • Producer
  • Consumer
  • Secondary consumer
  • Tertiary consumer
• Respiratory system measures oxygen, carbon dioxide, breathing rate
• The heart pumps blood around the body
• Xylem transports water and minerals from roots to leaves
• Phloem transports food (glucose) from leaves to other parts of the plant
• Arteries carry blood away from the heart, veins carry blood towards the heart
• Blood carries oxygen, nutrients, waste products and other substances around the body