Botanists call flowering plants angiosperms, from the Greek words for ... a tube down through the style and ovary and into the ovule, where fertilization occurs and a seed begins to grow.

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 ...

They discovered a new "gate" at the chalazal end of the ovule that regulates nutrient transport into the developing seed.