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.
Learn how the intrinsic pathway of apoptosis is triggered and regulated, from BCL-2 proteins and MOMP to cytochrome c release, apoptosome formation, caspase-9, and cell death.
Learn what platelets (thrombocytes) are, how they are formed, their structure and functions, normal platelet count, and their role in hemostasis and blood clotting.
Storage granules are bacterial cell inclusions that store carbon, phosphate, sulfur, and nitrogen reserves. Learn their types, structure, functions, formation, and identification.
Cilia are membrane-covered, microtubule-based projections that extend from the surface of many eukaryotic cells. Motile cilia generate movement of cells, fluids, or particles, whereas most primary cilia function as specialized sensory and signaling compartments. Their structure centers on an axoneme anchored to the cell by a basal body. What Are Cilia? Cilia are short hair-like … Read more
Learn the fluid mosaic model of the plasma membrane, including its definition, structure, components, features, membrane fluidity, evidence, limitations and modern modifications.
Learn what cell proliferation is, how the cell cycle and growth signals regulate it, how it differs from cell growth, and why it matters in development, tissue repair, and cancer.
Learn what the cell coat or glycocalyx is, its structure and composition, how it forms on the plasma membrane, and its major functions in protection, recognition and cell interactions.
Learn what meiosis is, how meiosis I and II reduce chromosome number, how crossing over creates genetic variation, and how meiosis differs from mitosis.
Learn what gametogenesis is, how germ cells form haploid gametes, and the stages, regulation, and key differences between spermatogenesis and oogenesis.