Buchner was successful in extracting a respiratory enzyme complex

Options

A. ATP
B. NADH
C. Zymase
D. Mitochondria.

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist and Context**: Edward Buchner was a German chemist known for his work on yeast and fermentation. He made a significant discovery in 1907 that led to a better understanding of cellular respiration.

2. **Understanding the Experiment**: Buchner was assisting his brother, who was conducting research on blood proteins. During this time, he prepared a yeast cell-free extract, which was intended for immunological applications.

3. **Addition of Sugar**: To preserve the yeast extract, Buchner added sugar. This step was crucial as it provided a substrate for fermentation.

4. **Observation of Bubbles**: After adding sugar, Buchner observed the formation of bubbles in the extract. This indicated that a fermentation process was occurring, leading to the production of carbon dioxide and alcohol.

5. **Identification of the Enzyme Complex**: The bubbles signified that an enzyme complex was at work. Buchner identified this enzyme mixture as "zymase," which is responsible for glycolysis—the process that converts sugar into alcohol and carbon dioxide.

6. **Conclusion**: Buchner's discovery of zymase was pivotal as it demonstrated that enzymes could function outside of living cells, leading to the understanding of fermentation and cellular respiration.

**Final Answer**: Buchner was successful in extracting a respiratory enzyme complex known as zymase.

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