What is the maximum concentration of alcohol which can lead to death of yeasts?

Options

A. 0.23
B. 0.06
C. 0.13
D. 0.26

Answer

To determine the maximum concentration of alcohol that can lead to the death of yeasts, we can follow these steps:

### Step 1: Understand the Role of Yeast in Fermentation
Yeasts, particularly Saccharomyces cerevisiae, are microorganisms that play a crucial role in the fermentation process. They convert sugars (like glucose) into alcohol (ethanol) and carbon dioxide through glycolysis and fermentation.

**Hint:** Remember that yeast ferments sugars to produce ethanol and CO2, which is why they are used in brewing and baking.

### Step 2: Identify the Process of Glycolysis
The process begins with glycolysis, where glucose is broken down into pyruvate. This pyruvate is then converted into ethanol during fermentation.

**Hint:** Glycolysis is the first step in cellular respiration and fermentation, leading to the production of pyruvate.

### Step 3: Determine the Alcohol Tolerance of Yeast
Yeast can tolerate a certain concentration of alcohol, but beyond a specific threshold, the alcohol becomes toxic to them. Research indicates that the maximum concentration of alcohol that can be tolerated by yeast is around 0.13 (13% v/v).

**Hint:** Think about how yeast can produce alcohol but also has a limit to how much it can withstand before it becomes harmful.

### Step 4: Conclude the Maximum Concentration
If the concentration of alcohol exceeds 0.13 (13%), it will lead to the death of the yeast cells due to the toxicity of alcohol, which disrupts cellular functions and leads to cell lysis.

**Hint:** Remember that exceeding the alcohol concentration of 0.13 will cause the yeast cells to die.

### Final Answer
The maximum concentration of alcohol which can lead to the death of yeasts is **0.13 (13% v/v)**.