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Cell Biology
Cell structure, organelles, cell division, biomolecules
Key Concepts
- Prokaryotic cells: no membrane-bound nucleus; no membrane-bound organelles
- Eukaryotic cells: membrane-bound nucleus; compartmentalised organelles
- Cell membrane: fluid mosaic model — phospholipid bilayer with embedded proteins
- Mitosis: 4 stages (PMAT); produces 2 identical daughter cells
- Meiosis: 2 divisions; produces 4 haploid gametes with genetic variation
Important Formulae
| Cell cycle phases | G₁ → S (DNA replication) → G₂ → M (mitosis) |
| Meiosis result | 1 diploid cell (2n) → 4 haploid cells (n) |
Quick Tips
- Ribosome: site of protein synthesis; 70S in prokaryotes, 80S in eukaryotes.
- Mitochondria and chloroplasts have their own DNA and ribosomes — support endosymbiont theory.
- Osmosis: water moves from low solute concentration (high water potential) to high solute concentration.
Practice Questions
Practice 20 randomly selected NEET questions on Cell Biology. Answers are revealed after each question.
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