Flagella Staining – Principle, Procedure, Result
Flagella can not be seen under a bright-field microscope by using ordinary stains. A simple and useful method has been used for visualization of flagella is known as wet mount technique.
Sourav Pan
Leifson Technique for Bacterial Flagella Staining
In 1930, Leifson introduced a simple flagella stain, using this stain he observed that mutations leading to nonflagellated from flagellated bacteria were common, as well as mutation leading to loss of motility without loss of the flagellum itself.
Thick and Thin Blood Smear Preparation
A blood smear is a simple diagnostic preparation where a drop of peripheral blood is spread on a clean slide, and it is dried for staining. It is the process used for observing blood cells and also for detecting parasites after staining methods like Giemsa. It is an important technique because it helps in demonstrating … Read more
Hanging Drop Method (Motility test) – Principle, and Procedure, Result, Uses
Hanging drop technique allows for the analysis of living microorganisms. This involves fixing the Microbial suspension into a drop of liquid over the slide of glass.
Bacterial Smear – Principle, Preparation Steps, Uses, Limitations
A bacterial smear is a thin layer of bacterial cell/culture which is placed on a clean, grease-free microscopic slide to observe a clear image under a microscope.
Kingdom Protista – Characteristics, Classification, Reproduction, Life Cycle, Examples
Kingdom Protista is described as a group of eukaryotic organisms which is neither plant nor animal nor fungus. It is the group that consists of organisms having a true nucleus and other membrane-bound organelles, and it is considered as the most diverse group among the eukaryotes. It is the historical classification used to place all … Read more
Hybridization –Types, Procedure, advantages, and limitations.
Hybridization is the process in which two organisms that belong to different varieties, subspecies, species, or even genera are crossed, and it results in the formation of a hybrid that carries genetic characters from both parents. It is the crossing that occurs naturally or by human interference where the genetic materials from two distinct parents … Read more
Native Polyacrylamide Gel Electrophoresis (PAGE)
Native PAGE is the method where proteins are separated in their original folded condition without any use of denaturing reagents. It is the process in which the movement of proteins in a polyacrylamide gel is controlled by the natural charge, size and the native conformation of the molecules. The proteins migrate through the gel matrix … Read more
Galactose (Gal) Operon – Structure, Regulation
What is Gal operon? The galactose operon is the unit in bacteria that is responsible for the metabolism of D-galactose, and it is organized with four structural genes (galE, galT, galK and galM). It is the process where these genes are required both for catabolic breakdown of galactose and for anabolic formation of compounds like … Read more
Origin of Chordates – Dipleurula concept, Echinoderm theory
It is considered that the origin of chordates is deeply associated with the deuterostome lineage, where the early ancestors are sharing characters with hemichordates and echinoderms. In this group, the basic features such as a notochord, dorsal hollow nerve cord (DHNC), pharyngeal gill slits, post-anal tail and endostyle are present at some stage of development. … Read more