What are the steps of bacterial staining?
What are the steps of bacterial staining?
The performance of the Gram Stain on any sample requires 4 basic steps that include applying a primary stain (crystal violet) to a heat-fixed smear, followed by the addition of a mordant (Gram’s Iodine), rapid decolorization with alcohol, acetone, or a mixture of alcohol and acetone and lastly, counterstaining with …
What is the structure of bacterial cell?
Bacterial Structure The numbered parts are: (1) pilus, (2) plasmid, (3) ribosome, (4) cytoplasm, (5) cytoplasmic membrane, (6) cell wall, (7) capsule, (8) nucleoid, and (9) flagellum (Source: LadyofHats [Public domain] via Wikimedia Commons). One of the most important structures of a bacterial cell is the cell wall.
What is the structure and function of a bacterial cell?
Cytoplasm – The cytoplasm, or protoplasm, of bacterial cells is where the functions for cell growth, metabolism, and replication are carried out. It is a gel-like matrix composed of water, enzymes, nutrients, wastes, and gases and contains cell structures such as ribosomes, a chromosome, and plasmids.
What is structural staining?
Structural staining allows you to observe certain structures on bacteria. This is important because. certain structures on bacteria can be antigenic or act as an endotoxin. Structural stains are more. complex than simple ones and use more than one stain to differentiate cellular components.
What are the 5 steps of Gram staining?
There are six basic steps:
- Apply a smear of bacteria on to a slide.
- Add about 5 drops of Hucker’s Crystal Violet to the culture.
- Add about 5 drops of iodine solution to the culture.
- Tilt slide and decolorize with solvent (acetone-alcohol solution) until purple color stops running.
- Add about 5 drops of Safranine O.
What is the principle of staining?
In positive staining, the surface of the bacterial cell takes on the colour of the stain. When basic stain is applied, there is an attraction between the negatively charged cell surface and positively charged chromophore, which leads to staining of the cell (Figure 3.2).
What are 6 structures of a bacterial cell?
A procaryotic cell has five essential structural components: a nucleoid (DNA), ribosomes, cell membrane, cell wall, and some sort of surface layer, which may or may not be an inherent part of the wall.
What stains are used in Gram staining?
[1] Often the first test performed, gram staining involves the use of crystal violet or methylene blue as the primary color. [2] The term for organisms that retain the primary color and appear purple-brown under a microscope is Gram-positive organisms.
Why is it important to understand the structure of bacteria?
Learning the structure of a microbe helps in understanding how a microbe functions. To drive this point home, here are a few examples. Disease causing bacteria (pathogens) have various structures that enhance their ability to cause illness. One important property is the ability to attach to the intended victim.
Why are bacterial cells stained?
Living bacteria are almost colorless, and do not present sufficient contrast with the water in which they are suspended to be clearly visible. The purpose of staining is to increase the contrast between the organisms and the background so that they are more readily seen in the light microscope.
What are the types of structural staining?
Types of staining techniques. Simple staining.
What is the process of Gram staining?
The Gram stain involves staining bacteria, fixing the color with a mordant, decolorizing the cells, and applying a counterstain.
- The primary stain (crystal violet) binds to peptidoglycan, coloring cells purple.
- Gram’s iodine (iodine and potassium iodide) is applied as a mordant or fixative.
