Life Process - 1 [ Cell Division : Meiosis ]



🧬 MEIOSIS 

Meiosis is a special type of cell division that happens only in sex cells (like sperm and egg). It reduces the chromosome number by half so that when fertilization happens, the number stays constant.

●Meiosis happens in two parts:

1. Meiosis I – Reduces the chromosome number (Diploid → Haploid)


2. Meiosis II – Like mitosis, splits sister chromatids




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✨ STEP-BY-STEP SIMPLE EXPLANATION

Meiosis I (Reduction Division)

➡ One diploid (2n) cell divides into two haploid (n) cells

1. Prophase I

Chromosomes become visible

Homologous chromosomes pair up

Crossing over happens (exchange of genes for variation)


2. Metaphase I

Paired chromosomes line up in the center


3. Anaphase I

Homologous chromosomes move to opposite sides


4. Telophase I

Two new haploid cells are formed



---

Meiosis II (Like Mitosis)

➡ Two haploid cells divide into four haploid daughter cells

5. Prophase II

Chromosomes condense again


6. Metaphase II

Chromosomes line up in the center


7. Anaphase II

Sister chromatids are pulled apart


8. Telophase II

Four haploid (n) cells are formed — all genetically different



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🔁 FLOW CHART OF MEIOSIS

Start with 1 Diploid Cell (2n)
          ↓
        Meiosis I
          ↓
  Homologous Chromosomes separate
          ↓
    2 Haploid Cells (n)
          ↓
        Meiosis II
          ↓
  Sister Chromatids separate
          ↓
     4 Haploid Daughter Cells (n)


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🖼️ DIAGRAM (Based on Your Textbook Images)

Here’s the combined diagram from your image explained clearly:

Meiosis I:

Prophase I: Chromosomes pair and crossing over

Metaphase I: Pairs line up in middle

Anaphase I: Pairs move apart

Telophase I: Two new haploid cells formed


Meiosis II:

Prophase II: Chromosomes condense again

Metaphase II: Line up again

Anaphase II: Sister chromatids separate

Telophase II: Four unique haploid cells form


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