Cytotaxonomy is based on :

Options

A. Cytological information
B. Chromosome number
C. Chromosome structure and behaviour
D. All

Answer

**Step-by-Step Solution:**

1. **Understanding Cytotaxonomy**: Cytotaxonomy is a branch of taxonomy that focuses on the classification of organisms based on cytological (cellular) characteristics.

2. **Cytological Information**: This includes details about the cells of organisms, such as their structure, number, and behavior. Cytotaxonomy uses this information to determine the phylogenetic relationships between different organisms.

3. **Chromosome Number**: One of the key aspects of cytotaxonomy is the chromosome number of an organism. Different species often have distinct chromosome numbers, which can be used to differentiate them.

4. **Chromosome Structure**: The physical structure of chromosomes, including their shape and size, is another important factor. Variations in chromosome structure can indicate evolutionary relationships.

5. **Chromosome Behavior**: The behavior of chromosomes during processes like meiosis (cell division) is also considered. This behavior can provide insights into how species are related.

6. **Conclusion**: Since cytotaxonomy relies on all of these factors—cytological information, chromosome number, chromosome structure, and behavior—the correct answer to the question is "all."

**Final Answer**: Cytotaxonomy is based on: all (cytological information, chromosome number, chromosome structure, and behavior).

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