What were the main features selected for Whittaker's five-kingdom classification?

Explanation

**Step-by-Step Text Solution:**

1. **Introduction to Whittaker's Classification**: Whittaker proposed a five-kingdom classification system to categorize living organisms based on certain criteria. The five kingdoms are Monera, Protista, Fungi, Plantae, and Animalia.

2. **Main Features Selected for Classification**:
- **Cell Structure**: The first feature is the type of cell structure. Organisms are classified based on whether they are prokaryotic (having no nucleus, like bacteria in Monera) or eukaryotic (having a nucleus, like those in Protista, Fungi, Plantae, and Animalia).

- **Body Organization**: The second feature is the organization of the body. This refers to whether the organisms are unicellular (single-celled) or multicellular (many cells). For example, Monera and some Protista are unicellular, while Fungi, Plantae, and Animalia are multicellular.
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