1.2

• Animal cells


  Typical cells that make up the human body
• Common features of all cells

  • Nucleus
  • Cytoplasm
  • Cell membrane
  • Mitochondria
  • Ribosomes
• Nucleus


  Controls all the activities of the cell and is surrounded by the nuclear membrane. It contains the genes on the chromosomes that carry the instructions for making the proteins needed to build new cells or new organisms
• Cytoplasm


  A liquid gel in which the organelles are suspended and where most of the chemical reactions needed for life take place
• Cell membrane


  Controls the passage of substances such as glucose and mineral ions into the cell. It also controls the movement of substances such as urea or hormones out of the cell
• Mitochondria


  Structures in the cytoplasm where aerobic respiration takes place, releasing energy for the cell
• Ribosomes


  Where protein synthesis takes place, making all the proteins needed in the cell
• Plant cells


  Very different organisms from animals. They make their own food by photosynthesis and do not move their whole bodies about from one place to another
• Features unique to plant cells

  • Cell wall made of cellulose
  • Chloroplasts
  • Permanent vacuole
• Chloroplasts


  Found in all the green parts of a plant. They contain the green substance chlorophyll which absorbs light so the plant can make food by photosynthesis
• Permanent vacuole


  A space in the cytoplasm filled with cell sap, important for keeping the cells rigid to support the plant
• Algae are simple aquatic organisms that make their own food by photosynthesis and have many similar features to plant cells
• Root cells do not have chloroplasts because they are underground and do not photosynthesise