Plant Classification

Jessica HarwoodDouglas Wilkin, Ph.D.

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Printed: January 14, 2015

AUTHORSJessica HarwoodDouglas Wilkin, Ph.D.

EDITORDouglas Wilkin, Ph.D.

CONTRIBUTORSDoris Kraus, Ph.D.Niamh Gray-WilsonJean Brainard, Ph.D.Sarah JohnsonJane WillanCorliss Karasov

www.ck12.org Chapter 1. Plant Classification

CHAPTER 1 Plant Classification• Explain how plants are classified.• Distinguish vascular plants from nonvascular plants.• Distinguish gymnosperms from angiosperms.

Do all plants grow from seeds?

No, there are actually a few plants that do not make seeds. Whether or not a plant makes seeds is one criteria usedto classify plants. How else could you distinguish between plants?

Plant Classification

Plants are formally divided into 12 phyla (plural for phylum), and these phyla are gathered into four groups ( Figure1.1). These four groups are based on the evolutionary history of significant features in plants:

1. Nonvascular plants evolved first. They are distinct from the algae because they keep the embryo inside ofthe reproductive structure after fertilization. These plants do not have vascular tissue, xylem or phloem, totransport nutrients, water, and food. Examples include mosses, liverworts, and hornworts.

2. Seedless vascular plants evolved to have vascular tissue after the nonvascular plants but do not have seeds.Examples include the ferns, whisk ferns, club mosses, and horsetails.

3. Gymnosperms evolved to have seeds but do not have flowers. Examples of gymnosperms include theRedwood, Fir, and Cypress trees.

4. Flowering plants, or angiosperms, evolved to have vascular tissue, seeds, and flowers. Examples of an-giosperms include magnolia trees, roses, tulips, and tomatoes.

Summary

• Nonvascular plants were the first plants to evolve and do not have vascular tissue.

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FIGURE 1.1The plant kingdom contains a diversity oforganisms.

• Seedless vascular plants have vascular tissue but do not have seeds.• Gymnosperms have seeds but do not have flowers.• Angiosperms have vascular tissue, seeds, and flowers.

Explore More

Use the resource below to answer the questions that follow.

• Plant Body Systems and Classification Part 1 at http://www.youtube.com/watch?v=6FnPVFPSt3A (7:21)

MEDIAClick image to the left or use the URL below.URL: http://www.ck12.org/flx/render/embeddedobject/57433

1. What plant groups are included in non-vascular plants2. Give an example of a seedless vascular plant.3. What groups of plants have seeds?4. What groups of plants have fruit?5. Where do you usually find non-vascular plants? Why?

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Review

1. What distinguishes the gymnosperms from other plants?2. What were the first types of plants to evolve?3. List the following major features of plants in the order they evolved: seeds, vascular tissue, flowers.4. Give two examples of seedless vascular plants.5. Give two examples of angiosperms.

References

1. Left to right, by row: Flickr:AvidlyAbide; S. Rae; Ray Bouknight; Flickr:Reza; Lori Branham; Mary T.Moore; Flickr:kanegen; Flickr:GaggieITMI; Flickr:kkmarais. Diversity of plants in the plant kingdom . CCBY 2.0

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