Biology Topic 1

• Fungi

  • Multicellular
  • Cells contain chloroplasts
  • Carry out photosynthesis and therefore make their own food (autotrophic)
  • Have cellulose cell walls
  • Store sugar as starch or sucrose
• Animals

  • Multicellular
  • Heterotrophic (get nutrition from feeding on other organisms)
  • Capable of movement from one place to another
  • Have nervous coordination
  • No cell wall or chloroplasts, do not photosynthesise
  • Store carbohydrate as glycogen
• Protoctists

  A strange collection of simple organisms that do not fit into the other groups, therefore often known as the 'dustbin' kingdom
• Protoctists

  • Some are like animals
  • Some are more like plants
  • Mostly single celled
• Bacteria

  • Small single celled organisms
  • Cell wall made of peptidoglycan
  • Some have a capsule or slime layer
  • Has no nucleus
  • Some species have flagella for movement
  • Some contain plasmids (small loops of DNA)
  • Have one circular chromosome
  • Some can do photosynthesis
• Pathogens

  Any organism or agent that can produce disease
• Bacteria

  Not made of cells, and do not carry out any of the normal 'characteristics' of living organisms
• Viruses

  All are parasites (live and reproduce in a host causing it harm)
• Viruses

  • Made of genetic material (DNA or RNA) surrounded by a protein coat
• All natural viruses cause disease. They can infect every type of living organism
• Nucleus

  Contains the genetic information of the cell
• Nucleus

  • Genetic information is in the form of chromosomes made of DNA
  • Parts of these chromosomes called genes determine what substances the cell makes
  • The nucleus controls the activities of the cell
• The nucleus controls the activities of the cell
• Cell membrane

  Forms a boundary between the cytoplasm and the outside of the cell
• Cell membrane

  • Some chemicals can pass through this barrier
  • The cell can control what comes in and out
  • It is partially permeable
• Cytoplasm

  Watery jelly like liquid which contains all of the organelles and enzymes
• Chemical reactions in the cell

  1. Take place in the cytoplasm

  2. Called metabolic reactions
• Mitochondria

  • Carry out the reactions of aerobic respiration
  • Release energy for the cell
• Cells that have a high demand for energy usually have many mitochondria, such as muscle cells
• Robosomes

  • Very very small particles
  • Found in the cytoplasm
• Robosomes

  Make proteins (protein synthesis)
• Proteins made by robosomes

  Are determined by the genes in the nucleus
• Chloroplast

  Contains chlorophyll
• Chlorophyll

  A green pigment
• Photosynthesis

  1. Absorbs light energy

  2. Makes food
• Cell Wall

  • Made of a non-living material called cellulose
  • Helps protect the cell and keep its shape
  • Freely permeable
• Cell walls of other organisms

  • Bacteria cell walls made of sugars and amino acids
  • Fungi cell walls made of chitin
• Vacuole

  Filled with cell sap
• Cell sap

  A store of dissolved sugars, mineral ions, and water