Pine Life Cycle

Conifer's Life Cycle

1. Both ovulate and pollen cones are found in the majority of conifer species. 2. Haploid microspores are produced by division of microsporocytes during meiosis. A microspore develops into a pollen grain (a male gametophyte enclosed within a pollen wall). 3. Ovulates' cone scales have two ovules that contain a megasporangium (a single ovule is depicted here). 4. When a pollen grain meets an ovule (pollination), a pollen tube is formed (germination) and makes its way through the megasporangium. 5. During development of the pollen tube, the megasporocyte goes through meiosis, resulting in four haploid cells, one of which develops into a megaspore. 6. The female gametophyte (containing achegonia which will develop into eggs) are formed from megaspores. 7. Once eggs have matured, the pollen tube, which contains two sperm cells, will have completed its development. The sperm meets the egg, the nuclei unite, and fertilization is complete. 8. Fertilization takes place more than a year following pollination. Even if all eggs are fertilized, only one develops into a zygote. The ovule develops into a seed containing the embryo, a food