Should you always use sterilized water for smear preparation?

Smear from Plate Be sure to use sterile water to dilute your samples. Regular tap water or the de-ionized water in your rinse bottles are often contaminated with bacteria.

1. Is it necessary to use sterile water when making a smear from a slant culture?
2. What are three important steps in a smear prep?
3. Why is it important that you don't put too much water to prepare the smear?
4. What is the importance of smear preparation?
5. Why is it necessary to add stain to a smear?
6. What are the two types of smear preparation?
7. What other methods of fixation can be used for smear preparation?
8. Why is it important to limit the quantity of cells used to prepare a smear?
9. Why is it important to use a small amount of bacteria when preparing a smear?
10. Why is it important to smear the blood as soon as the drop is placed on the slide?
11. What is smear preparation?
12. Why must slides used in smear preparation be grease free?
13. How long do you wash bacterial smear with alcohol?
14. Why are specimens to be stained suspended in sterile saline or distilled water?
15. Why do you rinse the slide with water after staining?

Is it necessary to use sterile water when making a smear from a slant culture?

It is not necessary to use sterile water when making the smear because if you use tap water which is not sterile the organisms will not hinder the smear from forming in any way. ... The major difference is that the agar slant technique needs a drop of water added to the slide since the microorganism is solid form.

What are three important steps in a smear prep?

In order to stain the bacterial specimen for microscopy one must first prepare the smear on the slide. This basically involves three steps----transferring a liquid suspension of the bacterium on the slide, drying the smear, and then heating slightly to firmly attach the smear to the slide.

Why is it important that you don't put too much water to prepare the smear?

The preparation of a bacterial smear can be difficult to learn. ... When mixing bacteria with water, if you over mix it can result in inaccurate cell patterns. 3. When heat-fixing, if you hold the slide over the flame too long, you will incinerate the cells.

What is the importance of smear preparation?

The preparation of a smear is required for many laboratory procedures, including the Gram-stain. The purpose of making a smear is to fix the bacteria onto the slide and to prevent the sample from being lost during a staining procedure. A smear can be prepared from a solid or broth medium.

Why is it necessary to add stain to a smear?

The main reason you stain a specimen before putting it under the microscope is to get a better look at it, but staining does much more than simply highlight the outlines of cells. Some stains can penetrate cell walls and highlight cell components, and this can help scientists visualize metabolic processes.

What are the two types of smear preparation?

Four different types of smear preparation methods (conventional method, blood film method, drop and rest method, and water-wash method) were carried out according to the standard reference as described below.

What other methods of fixation can be used for smear preparation?

2 The commonly used methods are air-dried and wet-fixed smears. Air- dried smears have many advantages over wet-fixed smears during routine cytology. They may be post- fixed after rehydration in saline with a variety of fixatives, such as ethanol/acetic acid, 95% ethanol or alcoholic formalin.

Why is it important to limit the quantity of cells used to prepare a smear?

why is it important to limit the quantity of cells used to prepare a smear? large amounts of cells in a smear can cause staining artifacts because stain is not washed away by destaining agents or water. ... heat fixation causes cells to adhere to the slide during staining.

Why is it important to use a small amount of bacteria when preparing a smear?

General Considerations. Just as in preparing a smear, you only need a small amount of organism. If you have too many organisms, you won't be able to see the morphology of individual cells.

Why is it important to smear the blood as soon as the drop is placed on the slide?

Common Causes of a Poor Blood Smear • As soon as the drop of blood is placed on the glass slide, there should be no delay in the making of the smear. Any delay, whatsoever, results in abnormal distribution of the white cells with many of the white cells accumulating at the thin edge of the smear.

What is smear preparation?

The first step in most bacterial staining procedures is the preparation of a smear. In a smear preparation, cells from a culture are spread in a thin film over a small area of a microscope slide, dried, and then fixed to the slide by heating or other chemical fixatives.

Why must slides used in smear preparation be grease free?

After removing the soapy filling with a clean cloth the surface becomes clean and grease free. If the slide is perfectly clean drop can spread on its surface in a thin even film, otherwise the water collects into small drops and film cannot be made.

How long do you wash bacterial smear with alcohol?

Rinse the slide with water. All cells are purple after this step. 5. Decolorize with 95% ethanol: let the alcohol run over surface of slide until no more crystal violet color comes out of the smear (time varies—no more than 5-10 seconds).

Why are specimens to be stained suspended in sterile saline or distilled water?

Specimens in laboratories are kept under sterile or distilled water to protect them from various contaminants.

Why do you rinse the slide with water after staining?

Crystal violet (a basic dye) is then added by covering the heat-fixed cells with a prepared solution. Allow to stain for approximately 1 minute. Briefly rinse the slide with water. ... This step washes away unbound crystal violet, leaving Gram-positive organisms stained purple with Gram-negative organisms colorless.