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
Methylene Blue Reduction Test
Methylene Blue Reduction Test (MBRT) is the test used for checking the microbiological quality of milk. It is the process where a redox dye called methylene blue is added to milk, and the time taken for disappearance of the blue colour is recorded. It is based on the activity of microorganisms present in the milk. … 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
Herdmania – Characteristics, Anatomy (With Diagram), Nervous System
Domain Eukaryota Kingdom Animalia Phylum Chordata Subphylum Tunicata Class Ascidiacea Order Stolidobranchia Family Pyuridae Genus Herdmania Authority Lahille, 1888 What is Herdmania? Herdmania is a solitary ascidian which is included under the Subphylum Tunicata of the Phylum Chordata. It is a sessile marine animal and the adult remains attached to hard substratum like rocks or … Read more
Ribozymes (RNA enzymes) – Definition, Structure, Function, Types
Ribozymes are catalytic RNA molecules, and it is the process where RNA itself act as an enzyme in different biochemical reactions. It is the first biological evidence that RNA can work both as a genetic material and also as a catalyst. This is referred to as the dual activity of RNA, and it gives support … Read more
Classification of Fish (pisces) – Systematic Classification and Based on feeding habit, habitat and manner of reproduction
A fish is an aquatic vertebrate which is mostly characterized by the presence of gills throughout life, a streamlined body, and paired as well as unpaired fins which helps in swimming. It is the group that comprises jawless forms like hagfish and lampreys, cartilaginous fishes like sharks and rays, and the bony fishes which is … Read more