Classification II: Principles and Dichotomous Keys

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

Lesson objectives

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

• Explain the principles and necessity of classification.
• Apply the rules of binomial nomenclature accurately.
• Construct and use a dichotomous key.
• Explain how classification reflects evolutionary relationships.

Summary

Classification II develops the Form 1 work into a practical skill: identifying organisms using a dichotomous key. A key offers a series of paired, contrasting statements, and each choice narrows the possibilities until one organism remains. Keys work only if the statements use observable, contrasting features and admit no overlap.