Gymnosperms
Gymnosperm leaves evolved into specialized reproductive structures called scales, cones are larger groups of scales. Male cones produce pollen, and the female cones produce eggs, and hold seeds. Unlike angiosperms, gymnosperms sit
seeds sit "naked" on the scales. There are three classes of gymnosperms, Conifera, Ginkgoae, and Cycadae.
seeds sit "naked" on the scales. There are three classes of gymnosperms, Conifera, Ginkgoae, and Cycadae.
Western Hemlock (Tsuga heterophylla)
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White Spruce (Picea glauca)
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Reproduction in Gymnosperms
The Classes
![Picture](/uploads/2/6/0/9/26098411/1397450896.png)
Conifers
- known as cone bearers or evergreens
- examples include: pines, fir, spruce, cedars, sequoias, redwoods, & yews.
![Picture](/uploads/2/6/0/9/26098411/1397450913.png)
Ginkgoes
- oldest seed plant
- one example is ginkgo biloba.
![Picture](/uploads/2/6/0/9/26098411/1397450947.png)
Cycadae
- palm-like plants
- found in tropical and subtropical regions.
- example includes: sycamore tree.
Interesting facts
- Did you know Conifers appeared in the fossil record about 290 million years ago?
- Conifers have approximately 588 living species!
- Cycadaes appeared in the fossil record about 230 million years ago!
- There are 220 species of cycadaes widely distributed through the tropical and subtropical regions.
- Cycadaes attained their greatest ecological importance during the Jurassic period, around 193 million to 136 million years ago, when they formed extensive forests!
- Did you know Ginkgoes are native to China but planted all over the world?
- Ginkgo is often referred to as a "living fossil" because they are nearly identical plants are known from fossils nearly 200 million years old.
- The Hemlock was named after a European weed which has a similar smell