Transcript Ch 22 Introduction to Plants

Calculate What percent of all plants are flowering
plants
2.
Interpret Graphs What is the second largest
group of plants
3.
Pose Questions What question about plant
evolution would you ask based on the data in this
graph
Graph also
on pg 530.
1.
CH 22 INTRODUCTION TO PLANTS
22.1 What is a Plant?
The Plant Kingdom
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Eukaryotes
Cell walls containing cellulose
Photosynthesis using chlorophyll a and b.
What Plants Need

Sunlight.
What Plants Need
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Sunlight
Way to exchange gases
with the surrounding
air.
What Plants Need



Sunlight
Way to exchange gases
with the surrounding air
Water and Minerals.
Origins in the Water


Ancestors were similar to today’s green algae
Green algae more closely related to plants.
The First Land Plants
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Biggest obstacle
 Getting

water
Grow close to the ground in damp locations.
An Overview of the Plant Kingdom

Five major groups based on four important
features:
 Embryo
formation, specialized water-conducting
tissues, seeds, and flowers.
Alternation of Generations

Shift between the haploid phase and the diploid
phase.
Sporophyte
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Multicellular diploid phase
Spore-producing plant.
Sporophyte
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Produces haploid spores through meiosis
Spores grow into multicellular structures called
gametophytes.
Gametophyte
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Multicellular haploid phase
Gamete-producing plant.
Gametophyte
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Produces reproductive cells called gametes
Sperm and egg fuse producing diploid zygote that
becomes a new sporophyte.
Trends in Plant Evolution
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Reduction in size of the gametophyte and the
increasing size of the sporophyte.