Pollen tube Pollen tube A pollen tube is a tubular structure produced by the male gametophyte of seed plants when it germinates. It acts as a conduit to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms. In maize, this single cell can grow longer than to traverse the length of the pistil. Pollen tubes were first discovered by Giovanni Battista Amici. They are used as a model for understanding plant cell behavior. Research is ongoing to comprehend how
Development of Spore pack has been revealed so far, called "galactic adventures" . It will include an adventure editor, as well as many new items and the ability for a player to go down to a planet's surface. On June 24, 2008, the "Spore: Galactic Edition" was announced. This special edition game is priced at $79.99, and includes a "Making of Spore" DVD video, a "How to Build a Better Being" DVD video, by National Geographic Channel (not included in all countries), a "The Art of Spore" hardback mini-book, a fold-out "Spore" poster and a 100-page Galactic Handbook. "Spore" extensively uses procedural generation,