Pollen grains consist of two cells: What is the difference between the generative cell and the tube cell?

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Pollen grains consist of two cells: What is the difference between the generative cell and the tube cell?
The generative cell has the nucleus which will divide to make the two sperm nuclei. One sperm nucleus will join with the egg nucleus to make the zygote and eventually the embryo. The other sperm nucleus will join with the two polar nuclei to make the endosperm.





The tube cell is a larger cell in the pollen, and this cell contains the tube nucleus. The tube nucleus directs the growth of the pollen tube from the stigma where the pollen landed, down through the style to the ovule inside the ovary of the pistil.





There are more detailed explanations on sites like the one listed below if you need more information.


http://www.biologie.uni-hamburg.de/b-onl...