Transcript Chapter 28 - plant classification

NAME THIS PLANT?
Ch. 28 Plant Evolution &
Classification
The first plants were thought to be water plants
 Algae. Other plants evolved from algae.
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Pg. 581
If you were to take algae out of the water would
it live alright.
So, how do land plants live away from water?
Land plants developed a cuticle, which is a
waxy protective covering, to protect against
desiccation. Bark & leaves have this.
Does algae have a cuticle?
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Algae is not a plant; it’s classified as a Protista
Vascular Tissue
Vascular tissues transport food and water throughout
the plant.
 1. Xylem – transports water. Dead cells.
 2. Phloem – transports food.
Table 30-1 Phyla of the Plant Kingdom (pg. 580)
 Nonvascular
 Vascular without seeds
 Vascular with seeds
Spores – haploid reproductive structure of some
plants.
Seeds – diploid (embryo) structure with a protective
coat and endosperm (food).
2 Main Groups of Plants
1. Nonvascular plants – no vascular tissue. No
true roots, leaves, or stems.
 Ex. Chlorophyta  Algae
 Ex. Bryophyta  Mosses
2. Vascular plants – have vascular tissues.
Able to transport food & water. They have true
roots, leaves, and stems.
 Pterophyta  Ferns (spores - seedless)
 Shenophyta  Horsetail (spores - seedless)
 Coniferophyta  pine trees (gymnosperms).
 Anthophyta  flowering plants
(angiosperms).
NAME THESE 2 PLANTS?
Bryophyta are mosses that have rhizoids.
Rhizoids (false roots) are like roots, but
they don’t have vascular tissue. How
many of you get moss on your fishing line
when you go fishing?
Horsetails have a cone-like structure at
the tip called a strobilius.
Horsetail is also called scouring rush;
Native Americans use to use it for clean
pots.
Name the main types of vascular plants
 Horsetail, ferns, conifers, flowering
plants
Parts of a Fern
Fern’s leaves are called  Fronds
Fern’s roots are called  Rhizomes
On the underneath side of a frond are several
round structures called  sori (plural).
The outside covering of the sori is a induisium.
The induisium opens up to release sporangium.
The sori hold several sporangium. Inside the
sporangium are spores, which are released
when the sporangium opens up.
Types of ferns  Pg. 587
Video Clip
Gymnosperms
Gymnosperm means “naked seeds”.
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Gymnosperms have cones with seeds.
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Video
Ginkgo trees are one of very few deciduous tree that
are gymnosperms.
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What does deciduous mean?
Has anyone ever heard of a ginkgo before?
Conifers or evergreens are the main type of tree in this
group  Coniferophyta.
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Oldest living organism – Bristle Cone Pine – 4,000 to 5,000
years old.
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Video
One of the most massive organisms – Giant Sequoia –
about 100,000 tons.
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Video
Angiosperms
Angiosperms – means “covered seeds”.
Anthophyta (division) – Flowering plants
 Divided into 2 Classes
 1. Monocotyledon (Monocots) – 1 seed leaf
or 1 cotyledon
 2. Dicotyledon (Dicot) – 2 seed leaves or 2
cotyledons.
Monocot Characteristics
 1. Parallel leaf venation. Ex. Corn & grasses
 2. 3 or 6 part arrangement of the flower
 3. 1 cotyledon
4. Scattered vascular bundles
 Examples = grasses, wheat, corn, tulips, etc.
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Dicot Characteristics
 1. Netted leaf venation. Ex. Most tree leaves
 2. 4 or 5 part arrangement of the flower
 3. 2 cotyledon
 4. Vascular bundles in a ring.
 Examples = trees, most weeds, etc.
What does the term deciduous mean?
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Trees that loose their leaves.
Alternation of Generation
This is the life cycle of plants (2 phases)
 1. Sporophyte Generation (Diploid)
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The time when the plant produces spores or seeds
 This is the mature part of the plants life cycle.
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2. Gameophyte Generation (Haploid)
The time when the plant produces an egg and pollen
(gametes).
 This is the part of the life cycle when there is a
antheridium (male plant) and archegonium (female plant).
 When the male (pollen ) fertilizes the female (egg), that
starts the sporophyte generation again.
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Pg. 582
Seeds vs. Spores
1. Seeds have a constant supply of food for the
embryo from the cotyledon.
2. Seeds are protected during harsh conditions.
 Drought & winter
3. Seeds adapt for easy dispersal.
 Stickers, dandelion, fruit, ect.
4. Seeds don’t require water.
So, how do spore plants survive if spores have
less advantages?
 Produce more spores