Specialised Cells

• The alveoli have thin walls that allow diffusion to occur quicker. They are surrounded by blood capillaries for a good blood supply and to keep the concentration gradient high. They are raspberry shaped to maximise surface area.
• Unicellular


  Made of a single cell
• Multicellular organism


  • Made of multiple cells
• Red blood cells


  • Found in the bloodstream
  • Carry oxygen through the bloodstream towards organs for respiration
• Red blood cells


  • Have a concave shape to increase surface area for oxygen to diffuse into
• Red blood cells


  • Have haemoglobin which picks up oxygen
• Red blood cells


  • No nucleus to make more room for oxygen
• White blood cells


  • Found in the bloodstream
  • Fight off disease
  • Able to engulf and destroy disease
• Nerve cell/neuron


  • Carry electrical impulses around the body
  • Very long to carry messages
  • Branches at the end to connect to other nerves
  • Have fatty cells around the nerve to insulate and keep the message on track
• Sperm cell


  • Carry male DNA to fertilise the ovum
  • Able to move easily
  • Have a ball of mitochondria to provide energy
• Root hair cell


  • Absorb minerals and water from the soil
  • Have a large surface area to absorb a lot of water
  • Have a thin cell wall so water can move through easily
  • No chloroplasts as they are not needed
• Palisade cell

  • Function is to perform photosynthesis
  • Found at the top of the leaf
  • Has lots of chloroplasts
• Ciliated cell

  • Function is to waft things along
  • Have cilia (hair like structures) that push things along
  • Found in the trachea to push dust and other waste out of the body
  • Found in the fallopian tubes and push the ovum towards the uterus
• Ovum cell

  • Function is to be fertilised by a sperm cell and form a zygote
  • Has a ‘yolk’ to provide early zygote with nutrients
• Muscle cell

  • Function is to contract and relax to allow body movement
  • Packed with mitochondria to provide energy for movement
  • Store glycogen (extra glucose after digestion) to be used later on around the cell