Chromosomes are the

Options

A. Physical basis of heredity
B. Physical basis of life
C. Chemical basis of heredity
D. Dynamic centres of the cells

Answer

**Step-by-Step Solution:**

1. **Understanding Chromosomes**: Chromosomes are structures within cells that contain DNA, which is the genetic material that carries hereditary information.

2. **Composition of Chromosomes**: Each chromosome is made up of DNA tightly coiled around proteins called histones. This structure allows for the efficient packaging of DNA within the cell nucleus.

3. **Role in Heredity**: Chromosomes play a crucial role in heredity. During cell division, chromosomes are replicated and segregated into daughter cells. This ensures that genetic information is passed from parent cells to offspring.

4. **Physical Basis of Heredity**: The term "physical basis of heredity" refers to the fact that chromosomes are tangible structures that carry genes. Genes are segments of DNA that code for specific traits, and these traits are inherited from parents to offspring.

5. **Conclusion**: Given the options provided, the correct answer is that chromosomes are the "physical basis of heredity." This is because they are the structures that physically carry and transmit genetic information from one generation to the next.

**Final Answer**: Chromosomes are the physical basis of heredity.

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