Today, there are 721 known gymnosperms. Conifers Conifers reproduce via woody structure called a cone. Most are evergreen and keep their leaves all year. That means they can photosynthesize on warmer, sunny winter days, and that they can take advantage of early spring sunshine when deciduous trees are putting out their new leaves. The needle-shaped leaves are also resistant to drought.
Conifers contain tracheids to conduct water.
Tracheids are also thought to have given rise to the shorter and wider cells called vessel elements which combine with fibres to make up xylem in angiosperms.