Gynosperms

Gymnosperms 720 species “naked seed” seeds not enclosed in any structure Cones called strobili Do NOT need water for sperm to reach egg- now covered to reduce water loss Pollen- enclosed sperm

Ginkgos- Ginkgophyta 1 species alive- Ginkgo biloba flourished during age of dinosaurs Fan-shaped leaves Resistant to air-pollution, insects, disease, highly planted in cities Seeds are thick and fleshy and produced on female trees

Ginkgos Figure 9.1: Ginkgo biloba (A) typical leaf; (B) pollen-bearing strobilus; (C) paired ovules on stalk at the point of pollination. Ovules continue to develop and fertilization takes place after ovules fall to the ground.

Ginkgos

Cycads- Cycadophyta 100 species alive- also flourished with dinosaurs Male and female plants Leaves resemble a palm tree Large cones Several species facing extinction

Cycads

Cycads

Gnetophyta 3 genera One or two strap-shaped leaves that split as the plant ages Ephedra- gives us the drug ephedrine

Ephedra

Conifers- Coniferophyta Pine trees Produce true cones Male cones are small, clustered and fleshy Female cones are large and become woody Leaves are needle-like