Question
Answer the following questions:
Explain the changes the primary oocyte undergoes while in different follicular stages before ovulation.
Explain the changes the primary oocyte undergoes while in different follicular stages before ovulation.
✓
Answer
Changes in the primary oocyte:
- Each primary oocyte gets surrounded by a single layer of granulosa cells and is known as primary follicle.
- Primary follicle get surrounded by more layers of granulosa cells and a new theca and form secondary follicle.
- A secondary follicle transforms into tertiary follicle characterised by a fluid-filled space, the antrum.
- Primary oocyte undergoes first meiotic division and produces two unequal haploid cells-a large haploid secondary oocyte and a tiny first polar body.
- The tertiary follicle further changes into the mature Graafian follicle.
- The secondary oocyte forms a new membrane called zona pellucida around it.
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