Why should the smear be rinsed with water?

Why should the smear be rinsed with water?

The decolorization of the cells is the most “operator-dependent” step of the process and the one that is most likely to be performed incorrectly. Rinse with water to stop decolorization. Rinse the slide with a counterstain (safranin or carbol fuchsin) which stains all cells red.

Why is it important to gently roll the swab across the slide when preparing a smear?

Roll the swab gently across the slide to avoid destruction of cellular elements and disruption of bacterial arrangements. Very thick or purulent specimens may be diluted in a drop of saline on the slide for easier smear preparation.

What is the important thing to prepare the bacterial smear?

Clean, grease free slides are needed for smear preparation. Grease or oil from the fingers on slides must be removed by washing the slides with soap and water. Finally rinse the slide with 95% alcohol and dry it.

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 are clean glass slides essential for the preparation of microbial smears Why must the glass slide be free of grease and oil before staining for flagella?

Why must the glass slide be free of grease and oil before staining for flagella? Because the grease and oil may interfere with the movement of the water and stain on the slide.

What is the purpose of drawing a circle on your slide before beginning?

It helps to initially draw a circle on the bottom of the slide so you know where to look for your smear. It is very easy to get confused which side of the slide your smear is on.

Why is it important to prepare a thin smear of bacteria?

Why is it important to make the smear thin? thin smear, because the thickness will determine whether or not you can visualize individual cell morphology(form), their arrangements, or details regarding gram reaction or internal structure. so that you can view individual cells by themselves rather than in a cluster.

Why is it important to fix the smear?

The purpose of making a smear is to fix the bacteria onto the slide. Fixing the bacteria will preserve the morphology of the cells long-term. Also, fixation assists the cells in adhering to the slide, so that the cells do not fall off the slide during the staining procedure.

Why is it important to air dry the bacteria before they are immobilized by heat fixation?

Why is it important to air dry the bacteria before they are immobilized by heat fixation? This ensures the optimal preservation of the bacterial morphology. Preparing smears disperses bacterial cells on a slide so that individual cells can be easily visualized under the microscope.

How to prepare an ideal bacterial smear for Culture?

PROCEDURE FOR PREPARING AN IDEAL SMEAR ⇒ Take a Clean, Grease free microscopic glass slide and mark the smear area on the underside of the slide with a glass marking pencil. ⇒ Flame the slide and place it on the disinfected table. For broth culture flame the slide on the same side on which the smear will be prepared.

How do you make a bacterial smear on a wax slide?

Placing the Bacterial Sample on the Slide Place a drop of water into the wax circle that has been created on the slide. Using a sterilized and cooled inoculation loop, obtain a very small sample of a bacterial colony. Gently mix the bacteria into the water drop.

Do you need to separate a bacterial smear?

If a simple stain of only one type of bacteria, or single mixed sample of bacteria is being prepared, no separation is required. Article Summary: In order to view individual bacteria through a light microscope, a bacterial smear must be attached to a slide and then stained. Here is the procedure.

What’s the best way to apply a blood smear?

Holding the spreader slide at an approximately 30-45º angle, back into the drop of blood and, as soon as you see the drop spreading along the edge of the spreader slide, push the spreader slide forward in a smooth, moderately fast motion; apply only enough