simple gram stain experiment

• what is primary added to the smear of bacteria


  crystal violet
• what is meant by crystal violet


  purple dye
• what colour will crystal violet turn a positive gram(+ve)


  purple
• what colour will crystal violet turn a negative gram(-ve)


  purple
• once the crystal violet has been added to the smear what will be added next


  grams iodine
• what colour will grams iodine turn the positive gram(+ve)


  purple
• what colour will grams iodine turn the negate gram(-ve)


  purple
• what is added to the smear after grams iodine was added and why

  alcohol wash to clear away the colour on the gram negative
• what effect will the alcohol wash have on the positive gram(+ve)


  it will stay purple
• what effect will the alcohol wash have on the negative gram(-ve)


  it will turn colourless
• what will be added to the smear after the alcohol wash has taken place


  safranin
• what effect will safranin have on the positive gram(+ve)


  it will stay purple
• what effect will safranin have on the negative gram(-ve)


  it will turn red/pink
• what will the colour of a positive gram be after a gram stain


  purple
• what will the colour of a negative gram be after a gram stain


  red/pink
• do positive grams contain lipopolysaccharides


  no
• do negative grams contain lipopolysaccharides


  yes
• what has a more complex cell wall a positive or negative gram


  a negative gram
• what will retain the crystal violet stain the positive or negative gram?


  the gram positive will retain the purple stain
• what is an example of a positive gram


  stapholococcus
• what is an example of a negative gram


  salmonella
• give the function of a thin petidoglycan cell wall


  structural support to prevent osmotic pressure causing lysis of bacterial cells