One of the following dinoflagellate is called night light :-

Options

A. Ceratium
B. Noctiluca
C. Navicula
D. Gymnodinium

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which dinoflagellate is referred to as "night light."

2. **Analyzing the Options:**
We need to evaluate each option provided to determine which one is known as "night light."

3. **Evaluating Keratium:**
- Keratium is a dinoflagellate with a cell wall made of cellulose.
- Its color is golden brown.
- It does not exhibit characteristics that would qualify it as "night light."

4. **Evaluating Noctiluca:**
- Noctiluca is a colorless dinoflagellate.
- It exhibits a holozoic mode of nutrition and is known for its bioluminescence.
- The bioluminescence is due to the presence of a pigment called Luciferin, which reacts with the enzyme Luciferase to produce light without heat.
- This light production causes Noctiluca to glow in the dark, resembling a burning fire at night.
- Therefore, Noctiluca is indeed referred to as "night light."

5. **Evaluating Nevicula:**
- Nevicula is a small boat-shaped diatom, not a dinoflagellate.
- Thus, it cannot be the answer to the question.

6. **Conclusion:**
Based on the evaluations, the dinoflagellate known as "night light" is **Noctiluca**.

**Final Answer: Noctiluca**

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