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 Action Potential? Definition of action potential An action potential is defined as a rapid, transient change in the electrical membrane potential of a neuron, characterized by a brief depolarization followed by repolarization. This process allows neurons to transmit signals over long distances. It occurs when the membrane potential reaches a critical threshold, leading … Read more
What is Neuronal Membrane? Components of Neuronal Membrane Cytosol and Extracellular Fluid The cytosol and extracellular fluid are essential environments for neuronal function, as they provide the medium for the movement of ions, which generate the electrical signals vital to neuron activity. The presence of water, along with ions dissolved in it, plays a critical … Read more
What are Dendrites? Definition of Dendrites Dendrites are branched extensions of neurons that receive and process incoming signals from other neurons, facilitating communication within the nervous system. They transmit electrical impulses toward the cell body and play a crucial role in integrating synaptic inputs to generate action potentials. Characteristics features of Dendrites The following characteristics … Read more
What is Axon? Definition of Axon An axon is a long, slender projection of a nerve cell (neuron) that transmits electrical impulses, known as action potentials, away from the neuron’s cell body to other neurons, muscles, or glands, facilitating communication within the nervous system. Characteristics features of Axon Axons are vital structures in the nervous … Read more
What is Neuroglia? Definition of Neuroglia Neuroglia, or glial cells, are non-neuronal cells in the nervous system that provide support, insulation, and protection for neurons. They play crucial roles in maintaining homeostasis, facilitating communication, and responding to injury or disease within the central and peripheral nervous systems. Classification of Neuroglia Neuroglia, or glial cells, are … Read more
What is Neuron? Definition of Neuron A neuron is a specialized cell in the nervous system that receives, processes, and transmits information through electrical and chemical signals. How Do Neurons Work? Neurons communicate through a combination of electrical impulses and chemical signals, ensuring efficient information transfer throughout the body. By facilitating the rapid transmission of … Read more
What is Neuroscience? Neuroscience is the scientific study of the nervous system, with a central focus on the brain. It explores how the brain and the network of nerves function at both the cellular and system-wide levels. Neuroscience is a multidisciplinary field, integrating approaches from molecular biology, physiology, cognitive psychology, engineering, and artificial intelligence. The … Read more
What is Recombinant DNA Technology? Definitions of Recombinant DNA Technology Recombinant DNA technology is a method used to manipulate and combine DNA from different sources to create new genetic combinations. It involves inserting genes from one organism into the DNA of another, allowing for the production of specific proteins or traits not naturally found in … Read more
The early detection of diseases is crucial for effective treatment, and molecular diagnostics serves as a pivotal tool in this regard. This term encompasses a range of diagnostic techniques that assess an individual’s health at a molecular level. Specifically, molecular diagnostics focuses on the identification and quantification of genetic sequences—often referred to as biomarkers—found in … Read more
Animal cells are ideal for recombinant protein production because they possess the ability to carry out post-translational modifications, a process that is often lacking in bacterial cells. This capability makes animal cells essential for the commercial synthesis of various biological products, including antibodies, hormones, growth factors, cytokines, and viral coat proteins, which are used in … Read more