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Significance of Mitosis & Meiosis | Class 11 Notes, MCQs  Comparison of Mitosis and Meiosis showing stages of cell division and chromosome behavior in Class 11 Biology. - Dr.Sanjaykumar Pawar  🌿 Significance of Mitosis (Equational Division) Mitosis is a type of cell division where one cell forms two identical daughter cells . It is also called equational division because chromosome number remains the same. Mostly occurs in diploid (2n) cells . In some lower plants and social insects, even haploid cells can undergo mitosis . 📌 Main Importance of Mitosis Mitosis produces genetically identical daughter cells (same DNA as parent cell). It is responsible for growth of multicellular organisms . As cells grow, the nucleus-cytoplasm ratio gets disturbed . So, mitosis helps to restore proper nucleus–cytoplasm balance . 🌱 Role in Growth and Repair Mitosis helps in increase in number of cells → growth of body . It is essential for repair and replacement of wo...

  Centrosome and Centrioles NEET Notes: 9×3 Arrangement Explained  Structure of centrosome and centriole showing the characteristic 9×3+0 microtubule arrangement and cartwheel organization. - Dr.Sanjaykumar Pawar  Centrosome and Centrioles  Centrosome Centrosome is a cell organelle present mainly in animal cells . It is located near the nucleus . A centrosome usually contains two centrioles . The two centrioles are surrounded by a protein-rich material called pericentriolar material (PCM) . The centrosome acts as the microtubule-organizing centre (MTOC) of the cell. It helps in the formation of spindle fibres during cell division. Structure of Centrioles Centrioles are cylindrical structures . The two centrioles in a centrosome are arranged perpendicular (90°) to each other . Each centriole shows a cartwheel-like arrangement . A centriole is made up of nine peripheral fibrils . These fibrils are composed of tubulin protein . Each peripheral fibri...