In anaerobic respiration, the number of ATP molecules produced are

Options

A. 1
B. 2
C. 3
D. 8

Answer

**Step-by-Step Solution:**

1. **Understanding Anaerobic Respiration**: Anaerobic respiration occurs in the absence of oxygen or in very low oxygen conditions. It is a type of respiration that allows organisms to generate energy without using oxygen.

*Hint: Remember that anaerobic respiration is crucial for organisms in low-oxygen environments.*

2. **Process of Anaerobic Respiration**: The process begins with the breakdown of glucose. Glucose is converted into two molecules of pyruvate (or pyruvic acid). This initial step is known as glycolysis.

*Hint: Glycolysis is the first step in both aerobic and anaerobic respiration.*

3. **ATP Production in Glycolysis**: During glycolysis, a net gain of 2 ATP molecules is produced for each molecule of glucose that is broken down into pyruvate.

*Hint: Focus on the fact that glycolysis is where the initial ATP is generated in both types of respiration.*

4. **Further Breakdown of Pyruvate**: In anaerobic conditions, the pyruvate is further converted into other products, such as ethanol and carbon dioxide in alcoholic fermentation, or lactic acid in lactic acid fermentation. However, this step does not produce additional ATP.

*Hint: The conversion of pyruvate in anaerobic respiration is important for regenerating NAD+, which is needed for glycolysis to continue.*

5. **Final ATP Count**: Since the only ATP produced during anaerobic respiration comes from glycolysis, the total number of ATP molecules produced from one molecule of glucose is 2.

*Hint: Remember that anaerobic respiration is less efficient than aerobic respiration in terms of ATP yield.*

**Final Answer**: In anaerobic respiration, the number of ATP molecules produced is 2.

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