five kingdom system of classification suggested by R.H whittaker is not based on

Options

A. Presence or absence of a well defined nucleus
B. Mode of reproduction
C. Mode of nutrition
D. Complexity of body organisation

Answer

### Step-by-Step Solution:

1. **Understanding the Five Kingdom Classification**: The five kingdom classification system was proposed by R.H. Whittaker in 1969. It categorizes living organisms into five distinct kingdoms based on certain criteria.

2. **Criteria Used for Classification**: Whittaker's classification is primarily based on three main characteristics:
- **Cell Complexity**: This refers to whether the organism has a well-defined nucleus (eukaryotes) or lacks a well-defined nucleus (prokaryotes).
- **Body Complexity**: This involves the organization of the organism, whether it is unicellular or multicellular.
- **Mode of Nutrition**: This includes how organisms obtain their food, such as autotrophic (self-feeding), heterotrophic (feeding on others), or saprophytic (feeding on dead organic matter).

3. **Evaluating the Options**: The question asks which aspect the five kingdom classification is NOT based on. The options provided are:
- Presence or absence of well-defined nucleus
- Mode of reproduction
- Mode of nutrition
- Complexity of body organization

4. **Analyzing Each Option**:
- **Presence or Absence of Well-Defined Nucleus**: This is a key factor in distinguishing between prokaryotes and eukaryotes, so it is included in the classification.
- **Mode of Reproduction**: This aspect is NOT considered in Whittaker's classification. The classification does not take into account how organisms reproduce.
- **Mode of Nutrition**: This is one of the main criteria used to classify organisms into kingdoms, particularly for the multicellular eukaryotes.
- **Complexity of Body Organization**: This is also a fundamental characteristic used in the classification, distinguishing between unicellular and multicellular organisms.

5. **Conclusion**: The five kingdom classification system proposed by R.H. Whittaker is NOT based on the mode of reproduction. Therefore, the correct answer to the question is "mode of reproduction."