Science

• Nucleus


  Controls the cell's activities and contains genetic material
• Cell membrane


  Controls the movement of substances into and out of the cell
• Cytoplasm


  Jelly-like substance where chemical reactions take place
• Mitochondria


  The site of respiration
• Ribosome


  Site of protein synthesis (proteins are made)
• Cell wall


  Strengthens the cell, made of cellulose
• Chloroplast


  Site of photosynthesis (contains chlorophyll, a green pigment which absorbs light)
• Vacuole


  Filled with cell sap to help keep the cell turgid (stiff) to provide support
• DNA


  The molecule that holds the genetic information in a cell
• Plasmid


  A small loop of DNA, only found in prokaryotic cells (bacteria)
• Eukaryotic cell

  DNA contained within nucleus (plant and animal)
• Prokaryotic cell


  DNA not contained in nucleus (bacteria)
• Cell differentiation


  Cells become specialised by developing different sub-cellular structures to help them function
• Chromosomes


  Found in nucleus of a cell, made of DNA. Usually found in pairs. Humans have 46 chromosomes (23 pairs) in a body cell
• Magnification


  Magnification = size of image / size of real object
• Red blood cells


  Transports oxygen in the blood
• White blood cells


  Cells in the blood that fight infection caused by pathogens
• Platelets


  Fragments of cells that cause clotting of blood at a wound
• Plasma


  The liquid part of the blood, with dissolved substances like glucose, proteins, ions and carbon dioxide
• Antibiotic


  Drug which cures bacterial disease by killing pathogenic bacteria
• Painkiller


  Drug which reduces pain, does not cure a disease but relieves symptoms
• Skin


  • Acts as a barrier, if damaged, repairs itself (scabs)
• Nose


  • Hairs and mucus trap pathogens before entering lungs
• Trachea and bronchi


  • Cilia cells (small hair-like projections from cells) and mucus (produced by goblet cells) trap pathogens
• Stomach


  • Contains hydrochloric acid to kill pathogens that have been eaten
• Vaccines


  Dead or weakened form of a pathogen injected into the body
• Antigen


  Protein on the surface of a pathogen which the body recognises as a foreign body
• Antibody


  Protein produced by white blood cells which binds to the antigens on the pathogen, and helps them be destroyed
• Herd immunity


  The protection given to a population against an outbreak of a specific disease when a very high percentage of the population have been vaccinated against it
• Measles

  • virus
  • symptoms fever, red skin rash
  • transmission is sneezing and coughing
  • to help have a vaccination