Ethanol is produced from starch as a raw material by the activity of

Options

A. Yeast
B. Protozoa
C. Virus
D. Rickettsia

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the production of ethanol from starch as a raw material and which organism is responsible for this process.

2. **Identifying the Process**: The conversion of starch into ethanol is known as fermentation. This is a biological process that converts sugars (in this case, derived from starch) into alcohol and carbon dioxide.

3. **Recognizing the Organism**: The primary organism responsible for the fermentation process that produces ethanol is yeast. Specifically, the yeast strain commonly used for this purpose is *Saccharomyces cerevisiae*.

4. **Chemical Reaction**: The fermentation process can be summarized by the following reaction:
- One molecule of glucose (C6H12O6) is converted into two molecules of ethanol (C2H5OH) and two molecules of carbon dioxide (CO2).
- The reaction can be represented as:
\[ C6H12O6 \rightarrow 2C2H5OH + 2CO2 \]

5. **Evaluating the Options**: The options provided are:
- a) Yeast
- b) Protozoa
- c) Virus
- d) Rickettsia
- Since yeast is the organism that facilitates the fermentation process to produce ethanol, it is the correct answer.

6. **Conclusion**: Therefore, the correct answer to the question is yeast.

**Final Answer**: Ethanol is produced from starch as a raw material by the activity of yeast.

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