Chapter 5: The Fundamental Unit of Life Test Test Time Explore various categories of non-fiction books. What are Living Organisms Made Up Of? Introduction to cells as the basic unit of life and their discovery by Robert Hooke. Cell Theory Schleiden and Schwann’s contributions; Virchow’s addition: all cells arise from pre-existing cells. Types of Cells Prokaryotic and eukaryotic cells — structure, differences, and examples. Plasma Membrane or Cell Membrane Structure and function; selectively permeable nature; osmosis and diffusion. Cell Wall Presence in plant cells; provides rigidity and protection; made of cellulose. Nucleus Control center of the cell; contains DNA, chromatin, nucleolus, and nuclear membrane. Cytoplasm Fluid portion of the cell where organelles are suspended and metabolic activities occur. Cell Organelles Various organelles and their functions: mitochondria, ER, Golgi bodies, lysosomes, plastids, vacuoles, ribosomes. Differences Between Plant and Animal Cells Comparison table of structural differences: presence of cell wall, plastids, shape, vacuoles etc.