Algae showing scalariform conjugation is

Options

A. Oedogonium
B. Spirogyra
C. Chlamydomonas
D. Ulothrix.

Answer

To answer the question "Algae showing scalariform conjugation is," we will follow these steps:

### Step 1: Understand the Types of Algae
First, we need to identify the different types of algae mentioned in the options: Oedogonium, Spirogyra, Chlamydomonas, and Eulothrix.

### Step 2: Identify Conjugation Types
Next, we should understand the types of conjugation that algae can exhibit. There are two main types mentioned: scalariform conjugation and lateral conjugation.

### Step 3: Focus on Scalariform Conjugation
Scalariform conjugation is characterized by a ladder-like appearance formed by conjugation tubes. It is primarily seen in certain species of algae.

### Step 4: Analyze Each Option
Now, we will analyze each option to see which one exhibits scalariform conjugation:
- **Oedogonium**: This type of algae does not show scalariform conjugation.
- **Spirogyra**: This algae is known for exhibiting scalariform conjugation, where two filaments align and form conjugation tubes resembling a ladder.
- **Chlamydomonas**: This type of algae does not exhibit scalariform conjugation.
- **Eulothrix**: This type of algae also does not show scalariform conjugation.

### Step 5: Conclusion
Based on the analysis, the only algae that shows scalariform conjugation is **Spirogyra**.

### Final Answer
The correct answer is **Spirogyra**.

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