Stage One: Becoming multicellular Stage Two: Developing sporangia Occurred in water Enables specialized tissues to develop Enables dispersal on land tage Three: Developing a large sporoph Confers competitive advantage Provides perennial spore production Stage Four: Removing dependence of fertilization on a film of water Enables survival in dry environments
Stage One: Becoming multicellular. Occurred in water. Enables specialized tissues to develop. Stage Two: Developing sporangia. Enables dispersal on land. Stage Three: Developing a large sporophyte. Confers competitive advantage. Provides perennial spore production. - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Stage One: Becoming multicellular
Stage Two: Developing sporangia
Occurred in waterEnables specialized tissues to develop
Enables dispersal on land
Stage Three: Developing a large sporophyteConfers competitive advantageProvides perennial spore production
Stage Four: Removing dependence of fertilization on a film of water
Enables survival in dry environments
Gymnosperms
naked seed
and the conifers (Pinophyta) .
Four major living groups
Cycads (Cycadophyta),
Welwitschia group (Gnetophyta),
Ginkgo, the Maiden Hair Tree (Ginkgophyta),
Stage Four: Removing dependence of fertilization on a film of water
Cycads and Welwitschia mirabilis
Reproduction is by seeds produced on open carpophylls or seed-bearing leaves.
Cycas bougainvilleana
Microcycas calocoma Photo Dennis Stevenson
Female cone
Lives in coastal desert regions of Namibia and Angola. Morning fogs provide moisture.
Female cones Male cones
Carbon-14 dating of the largest plants have shown that some individuals are over 1500 years old.
Ginko biloba
There are no native ginkgos living in the wild.
Illustration in Pen Tsao Kang Mu of Ginkgo with seeds (1578)
The only surviving species of a diverse group originating in the Permian
Ginko biloba- the wonder drug!
What, ginkgo? I thought that was just for old people who couldn't keep a train of thought? Nope, you're wrong. Ginkgo can be a very beneficial herb to bodybuilders as well.
http://www.teenbodybuilding.com/gingko.htm
Today everyone is looking for a way to enhance his or her workouts. So what can you do, well, take some Ginkgo Biloba.
In the Permian the land masses came together and formed a large continent call Pangea
Continental type climates typically have dry periods or seasonal rains. These can be seasonal and may be called monsoons
Gymnosperms show adaptations to drier conditions than ferns both in their reproduction and vegetative growth
1. Airborne male gametophyte (pollen) carried by wind to the female gametophyte. The fertilized egg is retained and protected by the sporophyte.
2. Production of a durable seed that at maturity consists of a protective seed coat, a source of nutrition and an embryo sporophyte all in one package.
3. Seed plants have wood producing tissue well developed for water conduction and support. This enables plants to grow tall and out-compete neighbors
Conifer adaptations for harsh environmentsReproductive
Vegetative
Xerophyte: a plant that can live where water supply is scanty or there is physiological drought
Fig. 50.11, p. 903
MONTANE CONIFEROUS FOREST
NORTHERN CONIFEROUS
FOREST
ALPINE TUNDRA
DECIDUOUS FOREST
TROPICAL FOREST
TROPICAL FOREST
TEMPERATE DECIDUOUS
FOREST
ARCTIC TUNDRA
Conifer distributionH
ighE
levationL
ow
Moisture Availability LowHigh
Life on the edge of the good times!
Zion CanyonPinus monophyllum
Tap roots stretch down 40 or more feet into the soil.
Very slow growth rates: a 6-10 inch diameter tree, 10 feet tall will be 80-100 years old.