Plant Anatomy

• Understand that plant anatomy is more than just roots, stems, leaves, and flowers, but rather, a study of the internal tissues and structures found within organs.
• Know the generalized differences between dicots and monocots.
• Draw and label cross sections of dicot and monocot roots.
• Draw and label cross sections of dicot and monocot stems.
• Draw and label cross sections of dicot and monocot leaves.

This teaching strategy for plant anatomy provides a two-hour presentation, with drawings, specimens, and visualizations to learn about dicot and monocot roots, stems, and leaves.

1. Introduce the topic of plant anatomy, explaining that this subject includes more than just roots, stems, leaves, and flowers but rather, the internal tissues and structures found within these plant organs. Focus on roots, stems, and leaves for this teaching material.
2. Ask participants to hypothesize what types of tissues and structures are found in roots, stems, and leaves. Pass around specimens of carrot roots, alfalfa or other stems, and spinach leaves. Point out major functions of these organs (roots – absorption of water and nutrients; stems – conduction of nutrients and connection for other organs; leaves – photosynthesis).
3. Starting with the carrot root, have participants examine the specimen with the naked eye and the begin discussing what tissues are found from the outer portion to the inner portion of the carrot.
4. Introduce the terms, epidermis, cortex, endodermis, and stele (with xylem and phloem). Draw a cross section of the root and label these tissues. Note that this is a cross section of a dicot root. See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
5. Explain how monocot roots differ from dicot roots and draw a cross section of the monocot root and label epidermis, cortex, endodermis, and stele (with xylem and phloem). See See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
6. Use the alfalfa or other stem as an example of a dicot and ask participants to examine the specimen with the naked eye and discuss what tissues are found from the outer portion to the inner portion of the stem.
7. Draw a cross section of a dicot stem. See See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
8. Draw a cross section of a monocot stem. See See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
9. Use the spinach leaf as an example of a dicot and ask participants to examine the specimen with the naked eye and discuss what tissues are found in the very thin layer of the leaf.
10. Draw a cross section of a dicot leaf. See See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
11. Draw a cross section of a monocot leaf. See See http://www.merlot.org/merlot/viewMaterial.htm?id=80106 for a simplified version of this cross section and http://www.merlot.org/merlot/viewMaterial.htm?id=80115 for more detailed visualizations.
12. Summarize this topic of plant anatomy, which addresses roots, stems, and leaves. Suggest to participants that they think about what part of a plant they are eating and which tissues are being consumed next time they are at the dinner table.

Supporting Files:

• Outline - Plant Anatomy (Microsoft Word 37kB Aug12 10)
• Questions - Plant Anatomy (Microsoft Word 33kB Aug12 10)

This teaching strategy provides discussion, as well as specimens and visualizations to learn about dicot and monocot anatomy. Participants learn about cross sections of roots, stems, and leaves to better understand the tissues found in these organs, how they are organized, and the differences observed in each. Incorporation of specimens and visualizations keeps the students interested in the topic. Having participants draw structures they can actually see and hold helps them stay active in the learning process.

Participants may be tested on their comprehension of this learning material through multiple choice, short-answer, or essay exams. A few example questions are embedded in this Activity Sheet, entitled "Questions – Plant Anatomy."

MERLOT description and link to "Atlas of Plant Anatomy," which features good micrographs from slides of plant structures. See http://www.merlot.org/merlot/viewMaterial.htm?id=80115

MERLOT description and link to "Plant Anatomy Atlas," which is a very simple, straightforward site that shows photomicrographs of dicot and monocot roots, stems, and leaves. See http://www.merlot.org/merlot/viewMaterial.htm?id=80106

MERLOT description and link to "Plant Anatomy Laboratory," which is a website that accompanies a textbook on plant anatomy. Photomicrographs of cells types and tissues may be found at this site. See http://www.merlot.org/merlot/viewMaterial.htm?id=76843