Life cycle of a conifer (pine)

1. Scales of pollen cones hold pollen sacs.
2. Meiosis of cells in pollen sacs yields microspores (n).
3. Microspores develop into pollen grains (male gametophytes) that are released and travel on the wind.
4. Scales of ovulate cones contain ovules.
5. Meiosis of cells in ovules yields megaspores (n).
6. Megaspores develop into egg-bearing female gametophytes inside the ovule
7. A pollen grain alights on a scale of an ovulate cone. It germinates and a pollen tube grows toward the ovule. Sperm form as the tube grows.
8. Fertilization produces a zygote that develops into a seed.
9. The seed germinates and grows into a new sporophyte