External Features of Plants

Syllabus tag: KCSE | Biology | Form 3 | Topic 1 Classification II

Lesson objectives

By the end of this topic, you should be able to:

• Describe the external features used to classify plants.
• Distinguish monocotyledons from dicotyledons by external features.
• Describe types of leaves, venation, phyllotaxy and root systems.
• Use external features to identify and group plant specimens.

Summary

Plants are identified from observable external features: the root system, the stem, and above all the leaf. Leaf shape, margin, venation and arrangement are the most useful, since they can be seen without dissection. Parallel venation with fibrous roots indicates a monocotyledon; network venation with a tap root indicates a dicotyledon.