Cell Nuclei in Ovule

[Edher]

Saludos,

I'm currently studying about the reproductive cycle of angiosperms.

I have a question about the female gametophyte. There is a point where it's made up of:

- Antipodal Cells
- Pollar Cells
- Synergids
- Egg

The polar nuclei, are they actually nuclei floating around the ovule? And if they are, of what cell are they nuclie of?

On that note, is the sperm discharged just nuclei with no surrounding cell?

Thousand Thanks,
Edher

[victor]

Actually what I know is...Megaspore do a karyokinesis three times and generate 8 cell which are divided into 3 cells at the kalaza point called antipoda, 2 cells at the microphyl point called sinergid, 1 cell floating at the center called ovum and 2 cells mixed into one called endosperm.

If the sperm of an angiospermae discharge in, they are divided into three parts..one for 'opening' the way to the megaspore, the other one is combined with ovum and the last one combined with endosperm.

for the development..sperm1 and ovum become zygot and then seed. then sperm2 and endosperm become flesh of the fruit.

That's what I know..hope this helps..