Oogenesis consists of

Options

A. Multiplication phase
B. Growth phase
C. Maturation phase
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Oogenesis**: Oogenesis is the process of female gamete (egg) formation in the ovaries. It involves several stages that lead to the development of a mature ovum.

2. **Phases of Oogenesis**: Oogenesis consists of three main phases:
- **Multiplication Phase**: In this initial phase, the primordial germ cells differentiate into oogonia. Oogonia undergo mitosis to increase their numbers.
- **Growth Phase**: After the multiplication phase, the oogonia develop into primary oocytes. This phase involves the growth of primary oocytes, which are arrested in prophase I of meiosis until ovulation occurs.
- **Maturation Phase**: In this final phase, the primary oocyte completes meiosis. It undergoes the first meiotic division to produce a secondary oocyte and a polar body. The secondary oocyte can then undergo the second meiotic division, which is completed only if fertilization occurs, resulting in a mature ovum and another polar body.

3. **Conclusion**: Therefore, oogenesis consists of all three phases: multiplication, growth, and maturation.

**Final Answer**: Oogenesis consists of all of the above phases.

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