00:01
In order to answer this question, let's talk about the staining.
00:03
It says, answer the following questions.
00:05
1.
00:05
To make the gram stain control a known gram -positive and non -gram -negative bacterial species.
00:13
Why is this important to have both types of, well, both types in the control? well, it is important to have controls because if the positive and negative controls are not as expected, then you cannot trust that the stain will perform properly.
00:30
And obviously as a positive control we use, known positive bacteria, and as a negative control, we use, known grand negative bacteria.
00:39
So this is the answer, practically, if you don't have control, or practically you have controls in order to be able to trust that this thing was performed properly.
00:48
The next question says, what was the purpose of applying 95 % alcohol during the staining process? so, for example, here you have grand positive and here you have gram negative.
00:58
The first staining or the first step is applied crystal violet.
01:03
This crystal biolidate is going to get into the peptidylacal layer of the cell wall of both bacteria, and they are both of the stain purple.
01:12
Then the second step is applied iodine.
01:15
Iodin is more than it is going to fix the crystal violet to the peptidoclican layer, so both are going to contain, or are going to continue being purple...