THE ESSENTIAL 20 FACTS FOR NEET
| # | Key Fact | Critical Detail |
|---|---|---|
| 1 | Interphase = ~95% of cell cycle | G1 + S + G2 |
| 2 | S phase: DNA doubles, chromosomes unchanged | 2C → 4C; still 2n |
| 3 | G2 phase: tubulin synthesised | For spindle formation |
| 4 | G0 examples: neurons, mature RBCs | Cannot divide |
| 5 | Mitosis = equational = PMAT | Produces 2 diploid identical cells |
| 6 | Prophase: condensation + nucleolus disappears | Spindle begins |
| 7 | Metaphase: chromosomes at equatorial plate | Via kinetochores |
| 8 | Anaphase (mitosis): sister chromatids separate | Centromeres SPLIT |
| 9 | Telophase: nuclear envelope reforms | Nucleolus reappears |
| 10 | Animal cytokinesis: cleavage furrow (centripetal) | Actin-myosin |
| 11 | Plant cytokinesis: cell plate (centrifugal) | Golgi vesicles |
| 12 | Meiosis = 2 divisions → 4 haploid cells | Reductional + equational |
| 13 | Prophase I substages: LZPDD | "Lovers Zealously Pursue Daring Dates" |
| 14 | Synapsis = zygotene | Bivalents form |
| 15 | Crossing over = pachytene | Non-sister chromatids |
| 16 | Chiasmata VISIBLE = diplotene | After synaptonemal complex dissolves |
| 17 | Terminalization = diakinesis | + nuclear membrane breaks |
| 18 | Anaphase I: homologous chromosomes separate | NOT sister chromatids |
| 19 | Anaphase II: sister chromatids separate | Like mitosis |
| 20 | After meiosis I: 2C, n; After meiosis II: 1C, n | Know the DNA content |
THE 3 BIGGEST NEET TRAPS
Trap 1: After S phase, DNA = 4C BUT chromosomes = STILL 2n (NOT 4n) Trap 2: Crossing over = PACHYTENE; Chiasmata VISIBLE = DIPLOTENE (NOT the same) Trap 3: Anaphase I separates HOMOLOGOUS CHROMOSOMES (NOT sister chromatids)
ONE-LINE MNEMONICS
- PMAT = "Please Make Another Taco" (mitosis stages)
- LZPDD = "Lovers Zealously Pursue Daring Dates" (prophase I substages)
- Pair in Z, Cross in P, See in D (Zygotene synapsis, Pachytene crossing over, Diplotene chiasmata visible)
- Animal=Constrict inward; Plant=Build outward (cytokinesis direction)
- S doubles D not Chr (S phase: DNA doubles, chromosomes don't)