Change in the number of body parts is called

Options

A. Meristic variation
B. Substantive variation
C. Continuous variation
D. Discontinuous variation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes a change in the number of body parts in an organism.

2. **Identifying Types of Variation**: There are different types of variations in biology, including:
- Meristic Variation
- Substantive Variation
- Continuous Variation
- Discontinuous Variation

3. **Analyzing Meristic Variation**:
- Meristic variation refers specifically to variations in the number of repeated body parts. For example, the number of petals in a flower or the number of segments in a worm.
- Since the question specifically mentions a change in the number of body parts, this term is relevant.

4. **Examining Substantive Variation**:
- Substantive variation affects characteristics such as shape, size, and color but does not involve changes in the number of body parts. Therefore, this option is incorrect.

5. **Understanding Continuous Variation**:
- Continuous variation refers to small, incremental changes that occur gradually over generations. These variations do not involve a change in the number of body parts but rather in traits that can be measured on a continuum (like height or weight). Thus, this option is also incorrect.

6. **Exploring Discontinuous Variation**:
- Discontinuous variation involves large, noticeable differences between individuals, such as blood type or flower color. While it can include variations in body parts, it does not specifically refer to the number of body parts. Hence, this option is also incorrect.

7. **Conclusion**: The correct answer to the question is "Meristic Variation," as it specifically refers to changes in the number of repeated body parts.

**Final Answer**: The change in the number of body parts is called **Meristic Variation**.

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