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.
Magnetic Stirrer is a laboratory device used to mix liquid solutions automatically without direct manual contact. It is also known as magnetic mixer. It works by producing a rotating magnetic field below the top plate of the instrument. The rotating magnetic field is produced either by a motorized spinning magnet or by stationary electromagnets. A … Read more
Centrifuge is a laboratory device that is used to separate different components of liquid or gas mixture on the basis of their density. It is commonly operated by an electric motor. The sample tubes are placed inside a rotor and the rotor rotates very rapidly around a fixed central axis. This rapid rotation produces centrifugal … Read more
Centrifuge is a mechanical device used to separate the components of liquid or gaseous mixture on the basis of their size, shape and density. It is operated by placing the sample mixture in tubes or containers which are fitted inside a rotor. The rotor is then rotated at very high speed around a fixed central … Read more
Centrifuge tube is a specialized tube that is used to hold liquid samples during centrifugation. It is made up of strong and durable material so that it can tolerate high rotational force without breaking or leakage. It is commonly used in biological, medical and chemical laboratories. During centrifugation, the tube is placed inside the centrifuge … Read more
Test tube is a simple laboratory glassware which is used in different laboratory works. It is a cylindrical tube like container, open at one end and closed at the other end. It is also called culture tube or sample tube. It is generally long and narrow in shape. The lower end may be rounded, flat … Read more
The most commonly used equipment is inoculation needles, transfer loops, inoculation, Bunsen burner, autoclave (or pressure cooker) incubators, hot air oven centrifuge, spectrophotometer magnetic stirrer electric shaker and rotary shaker heating plate, heating mantle distillation plant, UV-lamp carbon dioxide cylinder, water-bath and a single-pan balance that has weights (for general use) chemical balance, fine analytical … Read more
X-Ray Crystallography is an experimental technique used to know the three dimensional arrangement of atoms and molecules inside a crystal. It is used for studying the exact position of atoms. It also shows the chemical bonds and the total molecular structure present in the crystal. In this method, a focused beam of X-rays is passed … Read more
Electron Spin Resonance (ESR) is also known as Electron Paramagnetic Resonance (EPR). It is a non-destructive spectroscopic technique used for studying materials having one or more unpaired electrons. These unpaired electrons are present in paramagnetic substances. Every electron acts like a small magnet because it has intrinsic angular momentum or spin. When the sample is … Read more
Spectroscopy is a study of interaction of matter with electromagnetic radiation. It is used to study the atoms and molecules when they are exposed to different wavelength of light or energy. In this process, the atoms and molecules absorb, emit, reflect or scatter the radiation. These radiation are absorbed or emitted only at some specific … Read more
Ultracentrifuge is a high speed centrifuge which is used for separation of very small particles from a liquid medium. It can rotate at very high speed, usually more than 100000 rpm. Due to this high speed, very strong centrifugal force is produced. This force may be more than 1000000 times of gravity. Ultracentrifuge works on … Read more