Cell structure and Functions

• Phase contrast microscope


  Required to distinguish one part of cell from another
• Light microscope


  Contrast is often obtained by fixing and staining the material
• Micrometry


  Science related to measurement of dimensions and size of an object observing under microscope
• Micrometer


  • Special device of measurement attached or put into the microscope
  • Two types: ocular micrometer and stage micrometer
• Ocular micrometer


  Disc made up of glass with 100 equal divisions, placed in the eye piece of microscope
• Stage micrometer


  Calibrating device, a glass slide with proper scale like ruler
• Calibrating and estimating the size of a given object


  Image of ocular micrometer is super imposed on stage micrometer
• Micrometer is also called micron, the unit of micrometer is micron for length i.e.0.001 mm or about 0.000039 inches
• Cell wall


  Outer surface of some cells, non-living, stiff layer
• Cells with cell wall

  • Bacterial
  • Fungal
  • Algal
  • Plant
• Bacterial cell wall


  Made up of peptidoglycan
• Fungal cell wall


  Made up of modified polysaccharide chitin
• Plant and algal cell wall

  Made up of cellulose