The diploid sporophyte is dominant in life cycle of

Options

A. Volvox
B. Spirogyra
C. Chlamydomonas
D. Eucalyptus

Answer

To determine which plant has a dominant diploid sporophyte in its life cycle, we can follow these steps:

### Step 1: Understand the Life Cycle Stages
Plants have two main life cycle stages: the gametophytic stage and the sporophytic stage.
- **Gametophytic Stage**: This stage is haploid (n) and is responsible for producing gametes (sperm and eggs).
- **Sporophytic Stage**: This stage is diploid (2n) and produces spores through meiosis.

### Step 2: Identify the Characteristics of Each Plant
We need to evaluate the options provided:
1. **Volvox**: This is a green algae that exhibits a haplontic life cycle, meaning the gametophyte is the dominant stage.
2. **Spirogyra**: Another green algae with a haplontic life cycle, where the gametophyte is also dominant.
3. **Chlamydomonas**: This is also a green algae with a haplontic life cycle, where the gametophyte is dominant.
4. **Eucalyptus**: This is a flowering plant (angiosperm) that has a diploid sporophyte as the dominant stage in its life cycle.

### Step 3: Analyze the Dominance of Stages
In the case of the algae (Volvox, Spirogyra, and Chlamydomonas), the gametophyte stage is predominant, while in Eucalyptus, the sporophyte stage is dominant.

### Step 4: Conclusion
Based on the analysis, the plant that has a dominant diploid sporophyte in its life cycle is **Eucalyptus**.

### Final Answer
The diploid sporophyte is dominant in the life cycle of **Eucalyptus**.

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