For this semester, I need to know the whole process for
ovogénèse. Yes, it's in French and a lot more terminology below in this text will be for I am learning about this in that nomenclature. So I figured instead of just writing on the computer the story of what it is, I'll blog about it so I can come back to it later on and leave it out there on the Net if someone else ever finds it to help them as well.
Once upon a time.... there was a reproductive system in the human female body. In this reproductive system, there was magic which all starts in the ovaries. Within the ovaries,
ovules are formed. There are two zones within the ovaries, the
zone corticale which contains the
organites ovariens (
follicules and what derives from them to form the ovules) and the
zone médullaire, where we find the
paquet vasculo-nerveux that gives nourishment to the ovary.
A 7-month old female embryo is estimated to have 7 million primordial
follicules that form ovules in their ovaries. At birth, these contain only 1 million and by puberty 400,000 remain. The number just keeps going down until menopause. In the life of a woman, it is said calculate that only 300 to 400 follicules attain to a full ovulation cycle.
In the ovary, the primordial cells that will form ovules are called :
ovogonies. When one gets to a mature state, it's called
ovocyte 1.
Ovocyte 1 blocked in
Prophase 1 has a nucleus and a membrane. The
ovocyte 1 becomes surrounded by
des cellules folliculeuses aplaties within the stroms cortical, among the
capillaires sanguins. All these flatten out cells around the
ovocyte 1 multiply in number, while still surrounding the
ovocyte 1. Consequently, they become cubic shaped,
cellule folliculeuse cubique, these form the
Slavjanski membrane. From that point the whole
ovocyte 1 follicule enters in secondary phase. The
cellules folliculeuses cubiques multiply in layers around the
ovocyte 1 and this thickness of layers, underneith the
Slajvanski membrane, are called the
granulosa. While the
granulosa cells around the
ovocyte secrete a gel, this layer of gel around it becomes the zone
Pellucide. Starting from the middle going inside-out, you have the
ovocyte, the
Pellucide zone, the
granulosa, the
Slajvanski membrane, and last there is
la thèque interne. In
la thèque interne, there are
capillaires sanguins and
cellules épithéloïdes.
The next stage is called
jeune follicule cavitaire. Everything get bigger, especially because the cells of the
granulosa keep secreting the gel like matter. Little type-like puddles are form within the
granulosa which are called
corps de Call et Exner. When a whole punch of them gather together, it forms the
ANTRUM. The
follicule keeps getting bigger, more
epithéloïde cells attached themselves to
capillaires sanguins. Around the
thèque interne there is now a
thèque externe. The
thèque externe contains
myofibroblastes, which are hybrid cells that the
thèque interne doesn't have. Connexed inside the
antrum, the
ovocyte with the
pellucide zone and some layers of the
granulosa demarked themselves to become the
cumulus (or
oophorus). The cells from the
cumulus start secreting
hyaluronique acid, which accumulates in the atrium and the whole
follicule gets bigger, and become
préovulatoire. The
hyaluronique acid makes the cumulus detach itself from the
granulosa and as it's floating withing the
antrum, it become a
corona radiata.When the
follicule préovulatoire is at its biggest, an apex is form towards the
epithélium ovarien.
By Day 14 of the menstrual cycle, the ovulation period is where LH and RSH peak. This peak in LH necroses related tissues of the apex and the
follicule bursts. This sudden change of pressure withing the
antrum make the
myofibroblastes, of the
thèque externe, contract which pushes the
corona radiata outside of the ovary to become an ovule.
The
ovocyte 1 becomes now an
ovocyte 2 when expulsed. What's left behind in the
zone corticale of the ovary becomes the
corps jaune. The
Slajvanski membrane deteriorates from the
follicule, and this latter shrivels while the
thèque layers mingle with the
granulosa. Starting from the middle going inside-out of the
corps jaune, you have
coagulum central,
organisation fibreuse,
grandes cellules lutéales (which were the
granulosa),
petites cellules lutéales (which were the
thèque interne cells) and the
thèque. If the egg is fertilize, the
corps jaune will hang out in the ovary's
zone corticale to secrete the needed hormones for the fertilized egg until it can sustain itself in the endometer part of the uterus. If the ovule didn't meet it "prince charming" sperm, or when there's embryo, the
corps jaune degenerates and becomes a
corpus albican, or
corps blanc.
That's it! I'm not putting any pictures because I need to know this stuff by heart. When I read it, I see the images in my mind. Basically, I'm purposely making my brain work harder. Now for men this week!!!
