6. Diagram and list events of the cell cycle (interphase and mitosis) 7. Describe haploid, diploid, somatic cells, germ cells/gametes. (know human's diploid and haploid count) 8. Visually identify the stages of mitosis in a cell (prophase, metaphase, anaphase and telophase) 99 . Determine how the process of meiosis works. 10. Differentiate between mitosis and meiosis.

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```markdown
### 6. Diagram and List of Events of the Cell Cycle

#### Overall Cell Cycle
The cell cycle consists of:
- **Interphase** (preparation stage)
- **M Phase** (mitosis and cytokinesis)

A simplified diagram of the cell cycle:

┌─────────────┐
          │ Interphase  │
          │ (G₁, S, G₂) │
          └─────┬──────┘
                │
                ▼
          ┌─────────────┐
          │    Mitosis  │
          │ (Prophase,  │
          │ Metaphase,  │
          │ Anaphase,   │
          │ Telophase)  │
          └─────┬──────┘
                │
                ▼
          ┌─────────────┐
          │ Cytokinesis │
          └─────────────┘

#### Events in Detail

- **Interphase**
  - **G₁ Phase (Gap 1):**
    - Cell grows and synthesizes proteins.
  - **S Phase (Synthesis):**
    - DNA replication occurs: each chromosome duplicates to form two sister chromatids.
  - **G₂ Phase (Gap 2):**
    - Preparation for mitosis; cell checks for errors in DNA replication.
  
- **Mitosis**
  - **Prophase:**
    - Chromatin condenses into visible chromosomes.
    - The nuclear envelope begins to disassemble.
  - **Metaphase:**
    - Chromosomes line up along the cell’s equatorial plane.
    - Spindle fibers attach to the centromeres.
  - **Anaphase:**
    - Sister chromatids separate and are pulled toward opposite poles.
  - **Telophase:**
    - Chromosomes begin to de-condense.
    - Nuclear envelopes re-form around each set of chromosomes.
  - **Cytokinesis (often coupled with telophase):**
    - Division of the cytoplasm resulting in two daughter cells.

---

### 7. Definitions: Haploid, Diploid, Somatic Cells, and Germ Cells/Gametes

- **Diploid ($$2n$$) Cells:**
  - Contain two complete sets of chromosomes.
  - In humans, somatic (body) cells are diploid with $$2n = 46$$ chromosomes.
  
- **Haploid ($$n$$) Cells:**
  - Contain one complete set of chromosomes.
  - Human gametes (sperm and egg) are haploid with $$n = 23$$ chromosomes.
  
- **Somatic Cells:**
  - All body cells except the reproductive cells.
  - They divide by mitosis.
  
- **Germ Cells/Gametes:**
  - Cells involved in reproduction.
  - They are produced by meiosis and include sperm in males and egg cells (ova) in females.

---

### 8. Visually Identifying Stages of Mitosis

A diagram of the stages of mitosis (prophase, metaphase, anaphase, and telophase):

Prophase:            Metaphase:           Anaphase:            Telophase:
         ┌──────────┐         ┌──────────┐         ┌──────────┐         ┌──────────┐
         │          │         │          │         │          │         │          │
         │Chromatin │         │Chromosomes align│        │Sister chromatids separate│   │Chromosomes decondense│
         │condensing│         │at the cell center│       │moving to opposite poles│  │Nuclear envelope reforms│
         └──────────┘         └──────────┘         └──────────┘         └──────────┘

*Note: Actual cell images will display more complexity, but this diagram captures the essence of each stage.*

---

### 9. How the Process of Meiosis Works

Meiosis is a specialized cell division that produces gametes with half the number of chromosomes of the parent cell. It occurs in two rounds:

1. **Meiosis I: Reductional Division**
   - **Prophase I:**
     - Homologous chromosomes pair up (synapsis) and exchange segments (crossing over), increasing genetic diversity.
   - **Metaphase I:**
     - Homologous pairs line up along the cell equator.
   - **Anaphase I:**
     - Homologous chromosomes (each still composed of two sister chromatids) are separated.
   - **Telophase I and Cytokinesis:**
     - Two haploid cells are formed, each chromosome still consists of two chromatids.

2. **Meiosis II: Equational Division**
   - Resembles mitosis:
     - **Prophase II, Metaphase II, Anaphase II, Telophase II:**
       - Sister chromatids separate.
   - Results in four genetically distinct haploid gametes.

---

### 10. Differences Between Mitosis and Meiosis

- **Purpose:**
  - **Mitosis:** Produces two identical daughter cells for growth, repair, and asexual reproduction.
  - **Meiosis:** Produces four genetically different gametes for sexual reproduction.
  
- **Number of Divisions:**
  - **Mitosis:** One round of division.
  - **Meiosis:** Two consecutive rounds of division (Meiosis I and II).

- **Chromosome Number:**
  - **Mitosis:** Daughter cells are diploid ($$2n$$) if the parent cell is diploid.
  - **Meiosis:** Daughter cells are haploid ($$n$$) regardless of the parent cell's ploidy.

- **Genetic Variation:**
  - **Mitosis:** Produces cells that are genetically identical to the parent cell (barring mutations).
  - **Meiosis:** Produces cells with genetic variation due to crossing over and independent assortment during Meiosis I.

- **Occurrence:**
  - **Mitosis:** Occurs in somatic cells.
  - **Meiosis:** Occurs in germ cells to produce gametes.
```
**Cell Cycle and Cell Division Overview** 1. **Cell Cycle Stages:** - **Interphase:** Includes G₁ (growth), S (DNA replication), and G₂ (preparation for mitosis). - **Mitosis:** Divided into prophase, metaphase, anaphase, and telophase, followed by cytokinesis. 2. **Cell Types:** - **Diploid Cells:** Contain two sets of chromosomes (e.g., human somatic cells with 46 chromosomes). - **Haploid Cells:** Contain one set of chromosomes (e.g., human gametes with 23 chromosomes). - **Somatic Cells:** Body cells that divide by mitosis. - **Germ Cells/Gametes:** Reproductive cells that divide by meiosis to produce haploid gametes. 3. **Mitosis Stages:** - **Prophase:** Chromatin condenses, nuclear envelope breaks down. - **Metaphase:** Chromosomes align at the cell center. - **Anaphase:** Sister chromatids separate and move to opposite poles. - **Telophase:** Chromosomes decondense, nuclear envelope reforms. 4. **Meiosis:** - **Meiosis I:** Reduces chromosome number by half through homologous pairing and separation. - **Meiosis II:** Separates sister chromatids, resulting in four haploid gametes. - **Key Differences from Mitosis:** - Two rounds of division. - Produces genetically diverse gametes. - Occurs in germ cells. **Summary:** The cell cycle involves interphase and mitosis, with mitosis producing identical diploid daughter cells for growth and repair. Meiosis, occurring in germ cells, produces genetically diverse haploid gametes through two rounds of division.

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