Dichotomous Key Lab Activity Form
Objectives: After doing this lab activity, you should be able to:
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
identify bryophytes, pteridophytes, gymnosperms, and angiosperms.
describe the characteristics and classification of the four main plant divisions.
Materials:
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Four plant samples
Dichotomous key
Lab activity form
Hypothesis:
Before gathering your samples, predict the percentage of your plant samples that will be
bryophytes, pteridophytes, gymnosperms, and angiosperms.
Procedures:
Note: Read all the instructions for this lab before you begin working! Pre-reading the procedure
will give you a mental picture of what you will be doing and a better understanding of the
process.
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Find an area of vegetation, like a backyard or a park, and select four plants of different
characteristics from your chosen location. You may take pictures of your selected plants
or bring samples back to your home to study.
In the data chart below, list the location you discovered your plants and provide a
physical description of each of your four plant samples.
Use the dichotomous key provided to identify the phylum of your plant samples. List the
phylum for each in your data chart.
Answer the analysis and conclusion questions.
Data:
Location
Physical Description
Phylum
Plant sample 1
Plant sample 2
Plant sample 3
Plant sample 4
Analysis Questions:
1. What characteristics allowed you to identify each of your plant samples?
2. To which division does each of your plant samples belong and why? [Nonvascular
(Bryophytes), Seedless Vascular (Pteridophytes), Nonflowering Plants (Gymnosperms),
or the Flowering Plants (Angiosperms)]?
3. Was your hypothesis correct? Did you have more of one type of plant over another? If so,
why? Conclusion:
4. Why is it important to know the division or phylum of the various plant species growing
in your backyard?
Dichotomous Key
1
a. Vascular tissue is present- Veins in leaves and stems……...............Go to #3
b. Vascular tissue is not present ……………….......………………..Go to #2
2
a. Spongy, tiny leaf like appearance…………….…………Bryophyta (moss)
b. Horn-like structures…….….............………...................Anthocerophyta (hornworts)
c. Deeply grooved lobes…….………...………….….........Hepatophyta (liverworts)
3
a. Spores under or attached to leaves or stems…..………..Go to #4
b. Flowers or fruit…………….....………………..............Anthophyta (angiosperms)
c. Presence of cones……………………...……………....Go to #5
4
a.
b.
c.
d.
Grow in club-like clusters……………..…………............Lycophyta (club mosses)
Large fronds…………..………………………………...Pterophyta (ferns)
Stems with no leaves, whisk-like appearance….................Psilophyta (whisk ferns)
Reed-like appearance of leaves and stems.…....................Sphenophyta (horsetails)
5
a.
b.
c.
d.
Palm-like leaves, cone/s in the center…………….……..........Cycadophyta
White/silver fruit-like cones that emit foul odor…..…...............Female Ginkgophyta
Needle-like leaves and cones………………………..………Coniferophyta
Pollen tubes from one cone to another……………………….Gnetophyta