Answer:
The two important conditions that must be met before gram staining are-
1. The age of the culture should not exceed 24 hours.
2. Over heating, decolonization should be avoided.
Explanation:
Gram staining is a technique developed to distinguish the bacteria on the basis of the composition of the cell wall around the bacteria.
The gram stain is a sensitive technique so must be performed carefully. The precautions should be taken to avoid any error while gram staining that is-
1. Age of the culture- The culture should be freshly prepared just 18-24 hours before the experiment as above 24 hours bacteria lose their ability to retain the color so one would not be able to differentiate between the cultures.
2. While performing the experiment one should avoid overheating and decolorization with ethanol as both the factors lead to the loss of crystal violet stain from the cell and they take pinkish color after safranin staying.
Answer:
I believe the correct answer is B. Five
Prokaryotic cells don't have a nucleus
T cells. When HIV arrives in the lymph nodes – around 24 to 48 hours after exposure – they activate other immune cells, such as CD4 t-cells, HIV's primary target.
The answer is; C
A wetland in an area in the environment that is regularly or constantly inundated with water either from precipitation or due to proximity to riverbeds. Other than watersheds, other wetlands include marshlands, mangroves, lakes, rivers, and etc.