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  Cytoskeleton – Easy Notes for NEET  Cytoskeleton structure showing microtubules, microfilaments, and intermediate filaments inside a cell. - Dr.Sanjaykumar Pawar  Definition Cytoskeleton is a network of protein fibres present in the cytoplasm of a cell. It forms the internal framework or "skeleton" of the cell. It is made up of filamentous (thread-like) protein structures. Components of Cytoskeleton The cytoskeleton consists of three main types of fibres: Microtubules Long, hollow, tube-like structures. Made of the protein tubulin . Help in cell division and movement of cell organelles. Microfilaments Thin, solid fibres. Made of the protein actin . Help in cell movement and change in cell shape. Intermediate Filaments Fibres of intermediate thickness. Provide strength and stability to the cell. Help the cell resist mechanical stress. Location Present throughout the cytoplasm of eukaryotic cells. Forms a supporting network inside th...

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 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...

  Cell Theory and Overview of Cell – Easy NEET Notes (Line by Line) Schwann’s Contribution (1839) Theodor Schwann (1839) was a German zoologist . He studied different types of animal cells . He observed that animal cells have a thin outer covering . This outer covering is now called the plasma membrane (cell membrane) . Schwann also studied plant tissues . He found that plant cells possess a cell wall outside the plasma membrane. He concluded that the cell wall is a unique feature of plant cells . Based on his observations, Schwann proposed that: Plants and animals are made up of cells. Cells and their products form the body of organisms. NEET Point ✅ Schwann discovered the importance of the plasma membrane and recognized the cell wall as a characteristic feature of plant cells . Formation of Cell Theory Matthias Schleiden studied plant cells. Theodor Schwann studied animal cells. Together, Schleiden and Schwann formulated the Cell Theory . Main Idea ...