Characteristics of living organisms

• Nucleus


  Function of the nucleus
• Cell membrane


  Function of the cell membrane
• Tissue


  Definition of tissue
• Mucus


  Role of mucus in the trachea
• Cilia


  Role of cilia in the trachea
• Cell membrane


  Controls movement of substances into and out of the cell
• Cell wall


  Exerts a pressure to help maintain the shape of the cell
• Chloroplast


  Produces sugars using light as a source of energy
• Vacuole


  Withstands the internal pressure of the cell
• Nucleus


  Controls all the activities of the cell
• The enzyme catalase is found in lettuce leaves
• Investigating catalase activity


  1. Grinding lettuce leaves

  2. Adding to hydrogen peroxide solution

  3. Measuring volume of oxygen produced

  4. Reaction stops
• Enzymes


  • They increase the rate of chemical reactions without themselves being consumed or permanently altered by the reaction
  • They increase reaction rates without altering the chemical equilibrium between reactants and products
• Cell wall is present in plant cells but absent in animal cells
• Cells in dilute salt solution


  What happens when transferred to distilled water
• Phloem


  Tissue that transports sucrose in plants
• Magnesium deficiency


  • Decreases rate of sucrose movement out of leaves
  • Increases sucrose concentration in leaves
• Magnesium-deficient plants show symptoms of magnesium deficiency
• Features showing cicada is an insect

  • 1
  • 2
  • 3
• Arthropoda


  Group containing insects, crustaceans, arachnids and myriapods
• DNA


  Location of DNA in a cell
• Cicada species in New Zealand are in two separate groups
• DNA examination results


  Support idea of two migrations of cicadas from Australia to New Zealand
• Natural selection on islands

  1. Populations change over generations

  2. Become unable to breed with original populations