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1. What is a Cell? Cell is the structural and functional unit of life. It distinguishes living from non-living. All life processes occur inside cells. Cells can exist independently. 2. Discovery of Cell Robert Hooke (1665) – Discovered dead cells in cork. Anton van Leeuwenhoek – Discovered living cells. Robert Brown – Discovered nucleus. 3. Cell Theory Proposed by Schleiden and Schwann. Schleiden: All plants are made of cells. Schwann: All animals are made of cells. Modified by Rudolf Virchow: “All cells arise from pre-existing cells.” Final Cell Theory: All living organisms are made of cells. All cells arise from pre-existing cells. 4. Types of Cells (A) Prokaryotic Cells Found in Bacteria, Mycoplasma (PPLO). No nuclear membrane. No membrane-bound organelles. DNA present in nucleoid. Ribosomes: 70S. (B) Eukaryotic Cells Found in Protista, Fungi, Plants, Animals. True nucleus with nuclear membrane. Membrane-bound organelles present. Ribosomes: 80S (cytoplasm), 70S (mitochondria & c...

 Cell Biology, Plant Physiology, Reproduction in Plants, Ecology, Evolution, Biotechnology, Microbes, Biodiversity 📘 NEET Biology Mock Test Q1. Which cell organelle is directly involved in detoxification of drugs in liver cells? A. Golgi apparatus B. Smooth endoplasmic reticulum C. Lysosome D. Peroxisome Answer: B Q2. Cristae are absent in which of the following? A. Liver mitochondria B. Muscle mitochondria C. Prokaryotic cells D. Plant mitochondria Answer: C Q3. Which stage of cell cycle shows maximum protein synthesis? A. S phase B. G1 phase C. G2 phase D. M phase Answer: B Q4. Which enzyme is responsible for removal of RNA primer during DNA replication in prokaryotes? A. DNA ligase B. DNA polymerase I C. DNA polymerase III D. Primase Answer: B Q5. Pollen viability is longest in: A. Wheat B. Rice C. Rosaceae members D. Pea Answer: C Q6. Which structure guides pollen tube entry into embryo sac? A. Synergids B. Antipodals C. Egg cell D. Central cell Answer: A Q7. Double fertilizat...