Which of the following is an does not belong to green alga?

Options

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

Answer

To solve the question "Which of the following does not belong to green algae?", we need to identify the options given and classify them based on their characteristics. Here’s a step-by-step solution:

### Step 1: Understand the Types of Algae
Algae can be classified into three main groups based on their pigments:
- **Green Algae (Chlorophyta)**: Contains chlorophyll A and B.
- **Brown Algae (Phaeophyceae)**: Contains chlorophyll A and C, along with xanthophylls and carotenoids (e.g., fucoxanthin).
- **Red Algae (Rhodophyta)**: Contains chlorophyll A and D, and phycoerythrin.

### Step 2: Identify the Given Options
Assuming the options provided in the question include:
1. Volvox
2. Ectocarpus
3. Spirogyra
4. Chlamydomonas

### Step 3: Classify Each Option
- **Volvox**: A colonial green alga.
- **Ectocarpus**: A brown alga.
- **Spirogyra**: A filamentous green alga.
- **Chlamydomonas**: A unicellular green alga.

### Step 4: Determine the Odd One Out
From the classification:
- Volvox, Spirogyra, and Chlamydomonas are all types of green algae.
- Ectocarpus is a type of brown algae.

### Conclusion
The organism that does not belong to green algae is **Ectocarpus**. Therefore, the correct answer is option 2.

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