Cytoplasmic male sterility is passed down

Options

A. Through bacteriophage
B. Paternally
C. Maternally
D. Biparentally

Answer

**Step-by-Step Solution:**

1. **Understanding Cytoplasmic Male Sterility (CMS)**:
- Cytoplasmic male sterility refers to the condition in which plants are unable to produce functional male gametes (pollen) due to specific genetic interactions. This condition can be total (complete sterility) or partial (some functional gametes).

2. **Identifying the Cause of CMS**:
- CMS is primarily caused by interactions between nuclear genes (from the nucleus of the cell) and mitochondrial genes (from the mitochondria). These interactions are crucial for the development of functional anthers, which are necessary for pollen production.

3. **Inheritance Pattern of CMS**:
- The key aspect of CMS is its mode of inheritance. Unlike traits that are inherited from both parents, CMS is inherited through the cytoplasm, which is passed down from the mother plant. This means that the male sterility trait is maternally inherited.

4. **Evaluating the Options**:
- The options given are:
- A) Through bacteriophage
- B) Paternally
- C) Maternally
- D) Biparentally
- Since CMS is inherited through the cytoplasm, which is maternally derived, the correct answer is C) Maternally.

5. **Conclusion**:
- Therefore, the correct answer to the question "Cytoplasmic male sterility is passed down" is **maternally**.

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