The energy releasing process in which the substrate is oxidised without an external acceptor is called or Lactic acid converted into alcohol in process called

Options

A. glycolysis
B. fermentation
C. aerobic respiration
D. photorespiration

Explanation

To answer the question regarding the energy-releasing process in which the substrate is oxidized without an external acceptor, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Process**: The question asks about a specific type of energy-releasing process. In biological terms, this refers to a metabolic process that occurs in the absence of oxygen or an external electron acceptor.

2. **Identifying the Process**: The process in which the substrate is oxidized without an external acceptor is known as **fermentation**. Fermentation is an anaerobic process that allows organisms to produce energy when oxygen is not available.

3. **Types of Fermentation**: There are different types of fermentation, including alcoholic fermentation and lactic acid fermentation. The question mentions the conversion of lactic acid into alcohol, which is a specific type of fermentation.

4. **Lactic Acid to Alcohol**: The conversion of lactic acid into alcohol is not a common pathway in most organisms. Typically, lactic acid is produced during anaerobic respiration in muscle cells and is converted back to glucose in the liver. However, in some microorganisms, lactic acid can be converted to ethanol (alcohol) through a process called **lactic acid fermentation**.

5. **Conclusion**: Therefore, the energy-releasing process in which the substrate is oxidized without an external acceptor is called **fermentation**, and the conversion of lactic acid into alcohol occurs during **lactic acid fermentation**.

### Final Answer:
The energy-releasing process in which the substrate is oxidized without an external acceptor is called **fermentation**, and the conversion of lactic acid into alcohol occurs in a process called **lactic acid fermentation**.

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