Please do not put your backpacks, books, or clothes

on the tables where the microscopes are.

Thanks!

If you need a map for Saturday’s field trip, pleasepick one up from the front desk.

Gymnosperms(non-flowering seed

plants)

EKU BIO 131

Gymnosperms

• Phylum Ginkgophyta Ginkgo – the only species is Ginkgo biloba

• Phylum Cycadophyta the cycads

• Phylum Coniferophyta (or Pinophyta) the conifers

• Phylum Gnetophyta the gnetophytes

Ginkgoovule and seed development

Ginkgophyta

Leaves and seeds

microsporangiaon male tree

ripe seeds

cleaned seeds (sometimescalled “Ginkgo nuts”)

germinating seeds

Cycadophyta sporophytes

Two explorers with the only wildspecimen of Encephalartos woodii everdiscovered. It was first discoveredin the early 1700s.

Cycad cones

seed cones

pollen cones

Encephalartoswoodii

Cycad sporangia and coralloid roots

note microsporangium,tapetum, microspores

note integuments, megasporangium,Female gametophyte

coralloid roots root with zone of symbiotic cyanobacteria

ConiferophytaPollen cone buds of Japanese Black Pine (at about meiosis time)

photo by Ross Clark

pollen conebuds(the dark spotsare the tips ofthe microsporophylls)

buds containingneedles

Pine pollen developmentbe able to identify all structures

Coniferophyta

Pine ovule developmentbe able to identify all structures

Coniferophyta

Gnetophyta: Gnetum

notice stamens and ovules (plant is monoecious)

seeds

Gnetophyta: Ephedra

male female

(Ephedra is dioecious.)

seeds

Ephedrine is potentiallydangerous.

Gnetophyta: Welwitschia

Welwitschia is definitely one of the world’s most unusual plants!

Here is Welwitschia’s only habitat: the Namibian Desert, one of the driest deserts in the world.

Welwitschia is one ofThe world’s rarest plants. Most of the following photos were taken by Terry Huff, an EKU graduate student.

photo by Terry Huff

Gnetophyta: Welwitschia

photo by Terry Huff

Welwitschia has two leaves. They have basal meristems. The leaves eventually become separated into tattered segments.

Welwitschia is dioecious. This is a female plant. Note the ovulate (seed) cones, and compare them with the pollen cones on the next slide.

Here is a young plant. Young plants are extremely rare.Note the two leaves.

photo by Terry Huff

Gnetophyta: Welwitschia

photo by Terry Huff

Here is a male plant. Note the smaller pollen cones.

photo by Terry Huff

Gnetophyta: Welwitschia

photo by Terry Huff

photo by Terry Huff

Here are some female (seed)cones, together with the small bugs that live on Welwitschiaand may help to pollinate it.

photo by Terry Huff

Gnetophyta: Welwitschia

photo by Terry Huff

photo by Terry Huff

Here are some female cones, together with the small bugsthat live on Welwitschia and may help to pollinate it.

Here are some very young seed cones, at about pollination time.

photo by Terry Huff

Gnetophyta: Welwitschia

photo by Terry Huff

photo by Terry Huff

Here is another nice photo of a plant loaded with seed cones. Very few of the seeds germinate, because of the extreme environmental conditions in the Namibian Desert.

photo by Terry Huff

Why so many photos of Welwitschia?

-- because these photos by Terry Huff are some of the best photos ever taken of Welwitschia in its native habitat. They are better than any other photos you will find in any textbooks or on the web.

Terry said he was told there were fewer than 20 Welwitschia plantsremaining in their native habitat.