Red tide is caused due to

Options

A. Trichodesmium
B. Gonyaulax
C. Chlamydomonas
D. Desmid

Answer

**Step-by-Step Solution:**

1. **Understanding Red Tide**: Red tide is a phenomenon that occurs in marine environments where a significant increase in the population of certain microorganisms causes discoloration of the water, often appearing red or brown.

2. **Identifying the Organisms**: The organisms primarily responsible for red tides are dinoflagellates, which are a type of single-celled eukaryotes found in the Protista kingdom.

3. **Characteristics of Dinoflagellates**: Dinoflagellates are photosynthetic and can exhibit a variety of colors (yellow, green, brown, blue, or red) depending on the pigments they contain.

4. **Rapid Multiplication**: Certain dinoflagellates, such as Gonyaulax (often referred to in the context of red tides), can undergo rapid multiplication under favorable conditions, such as nutrient-rich waters.

5. **Resulting Phenomenon**: This rapid multiplication leads to a high concentration of these organisms in the water, which causes the water to appear red, hence the term "red tide."

6. **Conclusion**: Therefore, the organism responsible for the formation of red tides is specifically identified as dinoflagellates, with Gonyaulax being a notable example.

**Final Answer**: Red tide is caused due to dinoflagellates, specifically Gonyaulax.

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