Biology teacher

  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...

  Cilia vs Flagella: Easy NEET Biology Notes with Diagram & Mind Map  Structure of cilia and flagella showing the 9+2 microtubule arrangement and basal body in a eukaryotic cell. - Dr. Sanjay Kumar Pawar  Cilia and Flagella – Basic Idea Cilia and flagella are hair-like structures present on the surface of the cell. They are extensions of the cell membrane . Cilia Cilia are short and numerous hair-like structures . They move in a coordinated, oar-like motion (like rowing a boat). Function: Help in movement of the cell (e.g., Paramecium). Or move fluid/particles around the cell (e.g., in respiratory tract). Flagella Flagella are long, whip-like structures . Usually present in fewer numbers (1 or 2 per cell) . Function: Responsible for movement of the whole cell (e.g., sperm cell). Difference between Prokaryotic and Eukaryotic Flagella Prokaryotic flagella (bacteria) : Structurally different from eukaryotic flagella. Eukaryotic fla...