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Ovary: secondary follicle
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Primary oocyte nucleus <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P03.png)
Primary oocyte nucleus
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Zona pellucida <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P02.png)
Zona pellucida
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Cumulus oophorus <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P04.png)
Cumulus oophorus
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Antrum <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P01.png)
Antrum
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Stratum granulosum <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P05.png)
Stratum granulosum
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Theca interna <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P06-1.png)
Theca interna
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x
![Theca externa <p>The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x </p>](https://digitalhistology.org/wp-content/uploads/2018/03/O.R.F.OV_.09.P07-1.png)
Theca externa
The secondary follicle continues to grow, its multiple antral spaces coalescing into a single antrum. The primary oocyte remains arrested in prophase of the first meiotic division. It is surrounded by a ring of granulosal cells (the cumulus oophorus) and protrudes into the antral space. 400x