Presence of two chambered heart and gills in tadpole is example of

Options

A. Neo-Darwinism
B. Gause's law
C. Chargaffs law
D. Biogenetic law

Answer

### Step-by-Step Solution

1. **Understand the Question**: The question asks about the significance of the presence of a two-chambered heart and gills in a tadpole.

2. **Identify the Organism**: Recognize that a tadpole is the larval stage of a frog.

3. **Recall the Characteristics**: Note that tadpoles have a two-chambered heart and gills, which are features typical of fish.

4. **Consider Evolutionary Relationships**: Understand that frogs (as adults) evolved from fish, and thus, the tadpole retains some characteristics of its evolutionary ancestors.

5. **Examine the Options**: The options given are:
- Neo-Darwinism
- Gauss's law
- Zharkov's law
- Biogenetic law

6. **Evaluate Each Option**:
- **Neo-Darwinism**: This relates to the integration of Darwin's theory of evolution and Mendelian genetics, not specifically about embryonic development.
- **Gauss's law**: This law pertains to ecology and does not relate to evolutionary development.
- **Zharkov's law**: This is not a widely recognized law in biology.
- **Biogenetic law**: This law, proposed by Ernst Haeckel, states that the embryonic development stages of an organism reflect the adult forms of its evolutionary ancestors.

7. **Conclude**: Since the tadpole's features (two-chambered heart and gills) represent characteristics of its evolutionary ancestor (fish), the correct answer is **biogenetic law**.

### Final Answer
The presence of a two-chambered heart and gills in a tadpole is an example of **biogenetic law**.

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