Which of the following combinations of characters is true for slime moulds?

Options

A. Parasitic, plasmodium without walls, spores dispersed by air currents
B. Saprophytic, plasmodium with walls, spores dipersed by water
C. Parasitic, plasmodium without walls, spores dispersed by water
D. Saprophytic, plasmodium without walls, spores dispersed by air currents.

Explanation

To determine the correct combination of characters that is true for slime molds, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Nature of Slime Molds**:
- Slime molds are classified as saprophytic protists. This means they obtain nutrients by decomposing organic matter.

2. **Identify the Structure of Slime Molds**:
- The body of slime molds is known as plasmodium, which is a wall-less mass of multinucleated protoplast. This structure is free-living and thalloid in nature.

3. **Characterize the Plasmodium**:
- The plasmodium is covered by a slimy layer, which helps in its functioning. It does not have a cell wall, distinguishing it from many other organisms.

4. **Reproduction and Spore Formation**:
- Under unfavorable conditions, the plasmodium differentiates to form fruiting bodies that bear spores. These spores are produced at the tips of the fruiting bodies.

5. **Dispersal Mechanism**:
- The spores are dispersed by air currents, allowing for the spread of the slime molds to new environments.

6. **Evaluate the Given Options**:
- Now, we need to evaluate the options provided in the question based on the characteristics we have identified:
- **Option 1**: Incorrect, as it does not mention saprophytic nature.
- **Option 2**: Incorrect, as it states that the plasmodium has a wall, which is false.
- **Option 3**: Correct, as it accurately describes slime molds as saprophytic, with plasmodium without walls, and spores dispersed by air.
- **Option 4**: Incorrect, as it may not correctly represent the characteristics of slime molds.

7. **Conclusion**:
- The correct answer is the option that states slime molds are saprophytic, have plasmodium without walls, and produce spores that are dispersed by air.

### Final Answer:
The correct combination of characters true for slime molds is: **Saprophytic, plasmodium without walls, and spores dispersed by air.**

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