BIO B1

• Eukaryote


  A cell with a nucleus e.g. animal and plant cells
• Microscopy


  Using microscopes to magnify samples that cannot be seen with the naked eye
• Mitochondria


  A structure found in the cytoplasm of a cell where respiration occurs
• Prokaryote


  A cell without a nucleus e.g. a bacteria cell
• Ribosomes


  A structure found in the cytoplasm of a cell where protein synthesis occurs
• Sub-cellular


  Smaller than a cell
• Cells are the basic building blocks of any living thing or organism
• Types of cells


  • Eukaryotes
  • Prokaryotes
• Eukaryotes


  • Organisms or cells that have their genetic information stored as DNA in a sub-cellular structure called a nucleus
• Prokaryotes


  • Organisms or cells that have their genetic information found in a single DNA loop in a sub-cellular structure called plasmids
• Structures found in animal cells

  • Cytoplasm
  • Nucleus
  • Cell membrane
  • Mitochondria
• Structures found in plant cells

  • Cytoplasm
  • Nucleus
  • Cell membrane
  • Mitochondria
  • Cell wall
  • Permanent vacuole
  • Chloroplast
• Structures found in bacterial cells

  • Plasmid
  • Cell membrane
  • Ribosome
  • Capsule
  • Cell wall
  • Plasma membrane
  • Cytoplasm
• Ribosome


  0.02 μm
• Mitochondria


  0.5 μm
• Chloroplast


  1. 2 μm
• Prokaryotic cell


  0.1-5.0 μm
• Nucleus


  6 μm
• Eukaryotic cell


  10-100 μm
• One centimetre = 0.01 m = 1 x 10-2m
• One millimetre = 0.001 m = 1 x 10-3m
• One micrometre = 0.000001 m = 1 x 10-6m
• One nanometre = 0.000000001 m = 1 x 10-9m
• Electron microscopes have a higher magnification (up to x1,000,000) and better resolving power (up to 1 nm) than light microscopes
• Required practical 1 - use a light microscope to observe, draw and label a selection of cells


  1. Place sample on slide

  2. Stain if colourless

  3. Cover with cover slip

  4. Place slide on stage

  5. Use lowest magnification

  6. Adjust light and focus
• Magnification


  Eye piece x objective lens
• Size of object


  Size of image / magnification
• Cell differentiation is where cells become specialised with different sub-cellular structures to help them complete their function
• Examples of specialised animal cells

  • Muscle cells
  • Sperm cells
  • Nerve cells
• Root hair cells in plants have no chloroplasts as they are in the soil and will not have access to sunlight (UV) to photosynthesise
• Components of the vascular bundle in plants

  • Xylem
  • Phloem
• Xylem


  Moves water and dissolved minerals in the plant
• Phloem


  Moves glucose and amino acids around the plant
• Magnification


  How much bigger the microscope can make an object appear
• Resolution


  The detail that can be seen from the microscope