The pollen grain then germinates into a tube that guides the male reproductive cells to the depths of the ovary, picking up signals along the way that reveal the location of an ovule. Blocking signals ...

But many pollen grains can land on a stigma and germinate. So, how do plants ensure that each ovule is only penetrated by just one pollen tube? Using live cell microscopy along with special ...

a) Growth of pollen tube towards the ovule. Sperm cells exist at the tip of the tube. Pollen tube contents (PTC) are the liquid part of the pollen tube, shown in yellow. b) Upon pollination to the ...

A pollen grain starts to grow if it lands on the stigma of a flower of the correct species. A pollen tube grows through the style of the flower until it reaches an ovule inside the ovary.

En effet, après avoir produit ses ovules, le Ginkgo femelle reçoit du pollen que le ginkgo mâle produit en énorme quantité. Arrivé sur l'ovule, le grain de pollen germe et forme un tube pollinique ...