BIOL 2004 Lecture Notes - Lecture 5: Stamen, Sporophyte, Megaspore
Document Summary
The only living species of the phylum ginkophyta is the maiden tree (ginkgo biloba). It can grow to about 30 meters (about 100 feet). It has fan-shaped leaves, with two lobes, are similar to those of the maidenhair fern. Living ginkgos seem unchanged from ginkgo fossils that are 150 million years old. Megagamtophyte give rise to fleshy seeds that look like small plums. The so-called fruits are anatomically quite different from true fruits in angiosperms. The flesh is simply a seed coat rather than an ovary surrounding a seed. Like cycads and gnetophytes, gingko has separate ollen and seed-producing plants. In the united states- trees are commonly used for ornamental landscaping- typically only the pollen-producing trees. In asia, more seed-producing trees are grown because the seeds are popular in some cuisines. One such trait is the presence of vessel elements in addition to tracheas. Welwitschia and gnetum are similar to flowering plants in not having archegonia.
