2. Adaptations of Land Plant
Offspring develop from multicellular embryos that remain attached to the “mother” plant for protection and nourishment.
Vascular tissue is present in all but the bryophytes ( some of these have some type of transport vessels but lack TRUE roots, stems and leaves.

3. There are four main groups of land plants
Bryotphytes – mosses
Pteriodophytes – ferns
Gymnosperm – conifers
Angiosperms – flowering plants

4. Charophyceans are the green algae most closely related to land plants

5. Features that distinguish land plants.
Plasma membranes containing rosette cellulose – synthesizing proteins
Peroxisomes – help maximize the loss of organic products due to photorespiration.
Flagellated sperm are similar
Cell division – formation of phragmoplast

6. Five Characteristics Unique to Land Plants
Apical meristem – localized regions of active cell division in roots and shoots
Embryophtes – multicellular dependent embryos
Alternation of Generations
Walled spores produced in sporangia
Multicellular reproductive structures – antheridia and archegonia

7. What Is a Plant?
Multicellular eukaryotes that are photosynthetic autotrophs
Cell walls made of cellulose
Store surplus carbohydrates as starch
Mostly terrestrial

8. Terrestrial Adaptations Are Complimented by Chemical Adaptations
Secondary products
Synthesized by side branches of main metabolic pathway
Many protect the plant against excessive damage by herbivores
Examples
Cuticle
Lignin
Sporopollenin

9. Reproduction Plants produce their gametes within GAMETANGIA
Zygote develops into an embryo within a jacket of protective cells
Embryophytes – a key adaptation to the success of plants on land

10. ALTERNATION OF GENERATIONS
Occurs in life cycle of all plants
One generation is a multicellular haploid condition and the next is a multicellular diploid condition

11. Obstacles Plants Overcome
Absorb Minerals
Conserve Water
Cuticle
Stomata
Guard Cells
Reproduce on Land

12. A Vascular System Enables Plants to Thrive on Land
Most plants need a “plumbing” system to transport water, minerals and nutrients. This system is known as the VASCULAR SYSTEM.

13. Plants are monophylogenetic

14. Key to Modern Plant Diversity
There are four main periods of plant evolution. Each period was an adaptative radiation that follow the evolution of structures that open the new opportunities on land.
The first terrestrial adaptations included spores toughened by sporopollenin and jacketed in gametangia that protect the gametes.

15. The second major period was plant diversification in the Devonian period – earliest vascular plants lacking seeds
The third major period of evolution was the origin of the seed.
The fourth was the emergence of flowering plants.

16. Bryophytes the Liverworts the Hornworts the Mosses
Simplest of plants (gametophytes are dominate
Flat leafy body lacking cuticle, stomata, roots, stems or leaves
the Hornworts
Dominate gametophyte and have stomata
the Mosses
Small, most have simple vascular tissue
Sporophyte with slender stalk and spore capsule
“leafy” green gametophyte that lacks roots, stems and leaves

17. Bryophyta
Sphagnum moss
liverwort
moss
hornwort
Nonvascular, no true leaves roots and stems, root-like structures call rhizoids anchor plant to the soil, pioneer plants, gametophyte is the dominate generation

18. Moss genertations

19. Phylum Pterophyta Ferns are very divserse
Largest ferns are 82 feet tall with fronds 16 feet long
Leaves are called fronds
A fiddlehead is a tightly coiled new leaf
Underground stem called a rhizome

20. In vascular plants the branched sporophyte is dominant and is independent of the parent gametophyte.
The first vascular plants, pteridophytes, were seedless.
Vascular plants built on the tissue-producing meristems, gametangia, embryos and sporophytes, stomata, cuticles, and sproropollenin-walled spores that they inherited from mosslike ancestors.

21. Pteridophytes provide clues to the evolution of roots and leaves
Most pteridophytes have true roots with lignified vascular tissue.
These roots appear to have evolved from the lowermost, subterranean portions of stems of ancient vascular plants.
It is still uncertain if the roots of seed plants arose independently or are homologous to pteridophyte roots.
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22. The seedless vascular plants, the pteridophytes consists of two modern phyla:
phylum Lycophyta - lycophytes
phylum Pterophyta - ferns, whisk ferns, and horsetails
These phyla probably evolved from different ancestors among the early vascular plants.
Fig
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23. A homosporous sporophyte produces a single type of spore.
Ferns also demonstrate a key variation among vascular plants: the distinction between homosporous and heterosporous plants.
A homosporous sporophyte produces a single type of spore.
This spore develops into a bisexual gametophyte with both archegonia (female sex organs) and antheridia (male sex organs).
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24. A sporophyte-dominant life cycle evolved in seedless vascular plants
From the early vascular plants to the modern vascular plants, the sporophyte generation is the larger and more complex plant.
For example, the leafy fern plants that you are familiar with are sporophytes.
The gametophytes are tiny plants that grow on or just below the soil surface.
This reduction in the size of the gametophytes is even more extreme in seed plants.
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

26. Fig
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27. Ferns first appeared in the Devonian and have radiated extensively until there are over 12,000 species today.
Ferns are most diverse in the tropics but are also found in temperate forests and even arid habitats.
Ferns often have horizontal rhizomes from which grow large megaphyllous leaves with an extensively branched vascular system.
Fern leaves or fronds may be divided into many leaflets.
Fig d
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28. A heterosporous sporophyte produces two kinds of spores.
Megaspores develop into females gametophytes.
Microspores develop into male gametophytes.
Regardless of origin, the flagellated sperm cells of ferns, other seedless vascular plants, and even some seed plants must swim in a film of water to reach eggs.
Because of this, seedless vascular plants are most common in relatively damp habitats.
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

29. Coal powered the Industrial Revolution but has been partially replaced by oil and gas in more recent times.
Today, as nonrenewable oil and gas supplies are depleted, some politicians have advocated are resurgence in coal use.
However, burning more coal will contribute to the buildup of carbon dioxide and other “greenhouse gases” that contribute to global warming.
Energy conservation and the development of alternative energy sources seem more prudent.
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

30. Ferns produce clusters of sporangia, called sori, on the back of green leaves (sporophylls) or on special, non-green leaves.
Sori can be arranged in various patterns that are useful in fern identification.
Most fern sporangia have springlike devices that catapult spores several meters from the parent plant.
Spores can be carried great distances by the wind.
Fig a, b
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings