the cell

• Cell


  The smallest working unit of a living thing (organism)
• Cell


  • Made up of fat, protects the cell, allows substances in and out of the cell
• Nucleus


  Carries genes, which control the activities of the cell
• Cytoplasm


  Watery fluid of salts and food in which organelles float
• Mitochondria


  Where energy is released from food in respiration
• Ribosomes


  Makes proteins, e.g. enzymes and hormones
• Organelles in a cell

  • Mitochondria
  • Nucleus
  • Cytoplasm
  • Ribosomes
• The word cell was first used by Robert Hooke in 1666
• Cells come in all shapes and sizes. Skin cells are very different from heart cells, which are very different from nerve cells, which are very different from muscle cells
• All living things are made of cells
• Types of cells


  • Unicellular (made of just one cell, e.g. bacterial)
  • Multicellular (made of many cells, e.g. humans)
• Characteristics of life


  • Reproduction - making new living things
  • Respiration - releasing energy from food
  • Response - reacting to the environment
  • Growth - increasing in number or size of cells
  • Excretion - getting rid of waste matter
  • Nutrition - requiring food
  • Movement - changing position
• Plant cell


  • Has everything animal cells have
  • Has a cell wall made of cellulose, providing extra protection
  • Has a vacuole, a space in the cytoplasm where food and water are stored
  • Has chloroplasts, which contain chlorophyll and are involved in photosynthesis
• Parts of a plant cell

  • Nucleus
  • Cell wall
  • Vacuole
  • Cytoplasm
  • Mitochondria
  • Cell membrane
  • Ribosomes
  • Chloroplast