00:01
So everyone, in this question we will be discussing about gram staining, which basically is a differential stain which differentiates between the gram positive and gram negative bacteria.
00:15
So in this, a culture of the cell is taken and which is stained with crystal voilet, which is known as the primary stain because all the cells will carry.
00:30
This stain and will form a purple color and then after this the culture is treated with grams iodine solution which is a mordant and this increases the affinity of the affinity of the stain to the pescement so now we can clearly see the voilet color in dark.
01:06
After that the culture is treated with grams decolorizer, which is made up of ethyl alcohol plus acetyton.
01:25
And in this we will see that some of the cells have been decolorized, whereas the other cells are still purple in color by the crystal violet.
01:41
So these cells which are still purple in color are known as the gram positive bacteria.
01:50
And to confirm this, we add the secondary stain, which is saffronin.
01:57
So when we add the saffronin, we will see that the purple -colored bacteria.
02:04
Are still purple in color, but the bacteria which had lost its stain are now red in color.
02:16
So these bacteria which are now red stained are known as the gram negative bacteria...