Organization of the Organism

• All living things are made of cells
• Typical cells have:

  • Cell membrane: differentially or partially permeable to allow certain substances to enter and leave the cell.
  • Cytoplasm: where chemical reactions take place
  • Nucleus: contains DNA and controls the cell
  • Mitochondria: organelle where aerobic respiration happens
  • Ribosome: makes protein and can be found floating within the cytoplasm
• What do typical animal cells (e.g. the liver cell) have?

  cell membrane, cytoplasm, nucleus, mitochondria and ribosome
• Only plant cells have:

  • Vacuole: stores food & water & helps to maintain shape of cell
  • Cell wall: rigid to keep shape of cell
  • Chloroplasts: contain chlorophyll, which absorbs light energy for photosynthesis

  
• What do typical plant cells (e.g. the palisade cell) have?

  Vacuole, cell wall and chloroplasts
• Cell: red blood cell

  Function: transport of oxygen

  Adaptions: biconcave shape, no nucleus, flexible, has haemoglobin

  
• Cell: muscle cell

  Function: contracts to get structures closer together

  Adaptions: Long, many protein fibres in cytoplasm to shorten cell when energy available

  
• Cell: ciliated cell

  Function: move and push mucus

  Adaption: Tiny hairs called cilia

  
• Cell: root hair cell

  Function: absorb minerals and water

  Adaption: elongated shape for more surface area

  
• Cell: xylem vessel

  Function: transport water and support plant

  Adaptions: no cytoplasm so water passes freely, no cross walls so cells connect to form tube, lignin makes it strong and waterproof

  
• Cell: palisade cell Function: photo-synthesizes Adaptions: regular shape so many can fit in a small space, many chloroplasts

  
• Size of specimens equation

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