Sourav Pan is the founder and sole author of Biology Notes Online. He holds a Bachelor of Science (B.Sc.) degree and an M.Sc. in Microbiology from the University of Calcutta. He creates educational resources covering microbiology, immunology, biotechnology, genetics, cell biology, botany, zoology, and other life-science subjects.
His goal is to make complex biological concepts easier to understand through well-structured, student-friendly articles based on academic textbooks, peer-reviewed research, and authoritative scientific sources. In addition to writing new content, he regularly reviews and updates articles to improve their accuracy, clarity, and educational value.
What is Lineweaver–Burk plot? The Lineweaver–Burk plot, commonly referred to as the double reciprocal plot, stands as a foundational concept within the domain of biochemistry. Stemming from the renowned Michaelis–Menten equation, which pertains to enzyme kinetics, this plot was innovatively introduced by Hans Lineweaver and Dean Burk in the year 1934. Delving into its essence, … Read more
What is Induced Fit Model? Evidences Supporting Induced Fit Model The Induced Fit Model has garnered significant attention in the realm of biochemistry, and various pieces of evidence support its validity. This model posits that proteins, including enzymes, are not static or rigid structures. Instead, they exhibit dynamic properties, allowing them to adapt and change … Read more
What is Lock and Key Model? The Lock and Key Model Concept The “Lock and Key Model” is a fundamental concept in enzymology, introduced by Emil Fischer in 1899. This model provides an analogy to explain the specificity exhibited by enzymes during their interactions with substrates. In this analogy, the enzyme is likened to a … Read more
What are Vitamins? Definition of Vitamins Vitamins are organic molecules essential in small amounts for an organism’s proper metabolic function, which are typically obtained through the diet as they cannot be synthesized by the organism in sufficient quantities. History and nomenclature of Vitamins The history and nomenclature of vitamins have their roots in the early … Read more
The retinoids, a group of molecules related to the dietary retinol (vitamin A) , are essential for vision and reproduction, growth and the maintenance of epithelial tissue. They also play an essential part in the immune system. Retinoic acid, which is derived by oxidation of retinol plays a major role in the action of the … Read more
What is Vitamin D? Definition of Vitamin D Vitamin D is a fat-soluble secosteroid that plays a crucial role in calcium absorption in the gut, promoting bone health and regulating various other biological functions. It can be naturally obtained from sunlight exposure, certain foods, and supplements. Once ingested or synthesized in the skin, it undergoes … Read more
What is Vitamin E? Definition of Vitamin E Vitamin E is a fat-soluble antioxidant essential for human health that protects cell membranes from damage by reactive oxygen species and plays a role in immune function, skin health, and vision. It encompasses a group of eight compounds, including four tocopherols and four tocotrienols. Chemical structures of … Read more
What is Vitamin K? Definition of Vitamin K Vitamin K is a fat-soluble vitamin essential for the synthesis of proteins involved in blood coagulation and bone health. It is naturally found in green leafy vegetables, certain animal foods, and is also produced by gut bacteria. Properties of vitamin K Different forms of vitamin K Vitamin … Read more
What is Vitamin C (Ascorbic Acid)? Definition of Vitamin C (Ascorbic Acid) Vitamin C, also known as ascorbic acid, is a water-soluble essential nutrient found in various foods, primarily in citrus fruits. It plays a crucial role in tissue repair, collagen synthesis, and acts as an antioxidant, protecting cells from damage. Humans must obtain it … Read more
What is Vitamin B1 (Thiamine)? Definition of Vitamin B1 (Thiamine) Vitamin B1, also known as thiamine, is a water-soluble vitamin essential for the metabolism of glucose and amino acids in the body. It plays a critical role in energy production and is vital for the proper function of the nervous system. Thiamine is naturally found … Read more