Two different species of plants X and Y live together as if they are parts of the same plant Z. The plant X is an autotroph whereas plant Y is a saprophyte . The plant Y holds the cells of X in its mat of web-like hyphae and supplies water and minerals to cells of plants X . the plant X makes food by photosynthesis and shares it with plant Y
What could plants X be?

Answer

To solve the question regarding what plant X could be, we will analyze the information provided step by step.

### Step-by-Step Solution:

1. **Understanding the Characteristics of Plant X**:
- Plant X is described as an autotroph. Autotrophs are organisms that can produce their own food, typically through photosynthesis.

2. **Understanding the Characteristics of Plant Y**:
- Plant Y is identified as a saprophyte. Saprophytes obtain their nutrients from decaying organic matter, which means they cannot produce their own food.

3. **Analyzing the Relationship Between Plant X and Plant Y**:
- The question states that plant Y holds the cells of plant X in a mat of web-like hyphae. This indicates that plant Y is likely a fungus, as fungi have hyphae that form a network.

4. **Identifying the Role of Each Plant**:
- Plant X, being an autotroph, performs photosynthesis to create food. It shares this food with plant Y, which relies on plant X for nutrition.

5. **Recognizing the Symbiotic Relationship**:
- The relationship described is a symbiotic one, where both organisms benefit: plant X provides food for plant Y, and plant Y supplies water and minerals to plant X.

6. **Conclusion**:
- Given that plant X is an autotroph that performs photosynthesis and plant Y is a fungus (saprophyte), it can be concluded that plant X is likely an alga. In the context of symbiotic relationships, this combination of algae (autotroph) and fungi (saprophyte) is known as a lichen.

### Final Answer:
Plant X could be **algae**.