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Difference Between Prokaryotic and Eukaryotic Cells: NEET Notes for Beginners Comparison of Prokaryotic and Eukaryotic Cells with key structures explained for NEET Biology preparation. - Dr.Sanjaykumar Pawar  Bacterial Cell Structures (Continuation) Some bacterial membrane extensions help in: Cell division (formation of daughter cells) DNA replication and distribution Respiration Secretion processes Increasing surface area of plasma membrane Increasing enzyme content Chromatophores (in some bacteria) Found in cyanobacteria They are membrane extensions inside cytoplasm Contain photosynthetic pigments Help in photosynthesis Movement in Bacteria Some bacteria are motile (can move) Some are non-motile (cannot move) Flagella Long, thin, thread-like structures outside cell wall Help in movement (motility) Present only in motile bacteria Structure of flagellum Made of 3 parts: Filament → longest outer part Hook → connects filament to basal body ...

  Prokaryotic Cells Explained for NEET | Easy Biology Notes Labeled diagram of a prokaryotic cell showing nucleoid, plasmids, cell wall, and mesosome structure for NEET revision. - Dr.Sanjaykumar Pawar  1. Prokaryotes have a cell wall surrounding the cell membrane except in Mycoplasma. Most prokaryotic cells (bacteria) have a cell wall outside the plasma membrane. The cell wall gives shape and protection . Exception: does not have a cell wall. NEET Point: Mycoplasma is the smallest living cell and lacks a cell wall. 2. The semi-fluid matrix filling the cell is the cytoplasm. The inside of the cell contains a jelly-like substance called cytoplasm . It contains enzymes, nutrients, ribosomes, and other materials. Many metabolic activities occur here. 3. There is no well-defined nucleus. Prokaryotic cells do not have a true nucleus. Their genetic material is not enclosed inside a nuclear membrane. NEET Point: Prokaryotes have a nucleoid , not a true nucle...

 Cell Shape and Size Explained | Prokaryotic Cells NEET Biology Different cell shapes, cell sizes and prokaryotic cell types explained for NEET Biology preparation. - Dr.Sanjaykumar Pawar  UNIT OF LIFE – Cell Size, Shape and Prokaryotic Cells (Easy NEET Notes) 1. Different Shapes of Cells Red Blood Cells (RBCs) Shape: Round and biconcave disc. Biconcave means depressed in the center on both sides. This shape increases surface area for oxygen transport. RBCs carry oxygen to all parts of the body. Average diameter = about 7 µm. White Blood Cells (WBCs) Shape: Irregular and amoeboid. Amoeboid means they can change their shape. They move from blood vessels into tissues. WBCs help in body defense and immunity. Columnar Epithelial Cells Shape: Long, narrow and column-like. Found in the lining of stomach and intestine. Help in absorption and secretion of substances. Nerve Cell (Neuron) Shape: Branched and long. Consists of cell body, dendrites and axon. Ner...

  Cell Theory Explained: Schleiden, Schwann and Virchow Notes for NEET Cell Theory and Overview of Cell showing plant cell, animal cell, nucleus, cytoplasm and membrane-bound organelles. Cell Theory & Overview of Cell (NEET Notes for Beginners) 1. Development of Cell Theory 🧑‍🔬 Matthias Schleiden (1838) German botanist. Studied plant tissues. Concluded that all plants are made up of cells . 🧑‍🔬 Theodor Schwann (1839) German zoologist. Studied animal cells. Observed a thin outer boundary in animal cells, now called the plasma membrane (cell membrane) . Found that cell wall is present only in plant cells . Concluded that animals and plants are composed of cells and cell products . 📖 Cell Theory by Schleiden and Schwann They proposed that: All living organisms are made up of cells. Cells are the basic structural units of life. 🧑‍🔬 Rudolf Virchow (1855) Explained how new cells are formed. Proposed: "Omnis Cellula e Cellula" → All cells arise...