Question

Ethanol is commonly prepared by the _____ of certain sugars by yeast.

Short answer

Ethanol is commonly prepared by the \(fermentation\) of certain sugars by yeast.

Step-by-step solution

Identify the process by which yeast converts sugars to ethanol

The process by which yeast breaks down sugars and produces ethanol is called fermentation. In this process, yeast mainly consumes glucose (a type of sugar) and produces carbon dioxide gas along with ethanol as the waste product.

Fill in the blank with the correct term

Now that we know the process is called fermentation, we can complete the sentence from the exercise. Ethanol is commonly prepared by the fermentation of certain sugars by yeast.

Key concepts

Yeast

Yeast is a single-celled microorganism, scientifically classified as a fungus, vital to many industries, especially baking and brewing. In the context of ethanol production, Saccharomyces cerevisiae, or brewer's yeast, is the most commonly utilized strain.

Throughout history, humans have harnessed the natural capabilities of yeast to ferment sugars into ethanol and carbon dioxide. This biological process occurs under anaerobic conditions— in environments lacking oxygen. Yeasts convert carbohydrates — primarily glucose, fructose, and sucrose — into cellular energy, which results in the byproducts that include ethanol, a form of alcohol.

Yeast's ability to ferment sugars is not only crucial for the production of alcoholic beverages but also significant in biofuel industries. The understanding of yeast metabolism and its genetic manipulation has led to strains that can efficiently produce ethanol from various sugar sources, making it a centerpiece in renewable energy research.

Ethanol Production

Ethanol production refers to the method by which ethanol is generated, most commonly through the fermentation process. In the case mentioned in the exercise, ethanol is produced by the fermentation of sugars by yeast. This is a widespread method, particularly in the production of alcoholic beverages and biofuels.

Steps Involved in Ethanol Production

Initially, carbohydrates from plant materials like corn, sugarcane, or wheat are broken down into simple sugars. In a controlled environment, yeast is added, which begins the fermentation. The yeast organisms feed on the sugars, and through a biochemical reaction, they produce ethanol and carbon dioxide as primary byproducts.

This resulting ethanol can be used in various applications, including as a fuel additive to gasoline, as it burns cleanly and reduces greenhouse gas emissions. Additionally, advances in technology have streamlined the process, making ethanol a more cost-effective and environmentally friendly option.

Biochemical Processes

Biochemical processes are intricate sequences of chemical reactions that occur within living organisms. These processes are fundamental to life, enabling organisms to grow, reproduce, maintain their structures, and respond to their environments.

Fermentation is an example of a biochemical process where yeast breaks down sugars without the need for oxygen. Instead of the complete breakdown of glucose to water and carbon dioxide (as seen in aerobic respiration), fermentation results in the production of ethanol and a lesser amount of energy. The equation for the fermentation of glucose can be represented as: \[ C_6H_{12}O_6 \rightarrow 2 C_2H_5OH + 2 CO_2 + energy \]

Understanding these processes gives scientists the tools to develop new technologies and improve existing ones. For example, metabolic engineering of yeast cells allows for increased ethanol yields and more efficient fermentation processes, which is significant given the rising demand for renewable energy sources and sustainable practices.