Glycolysis Practice: Cellular Respiration Quiz

Explanation
Acetyl-CoA does not enter fermentation. Instead, it is converted into carbon dioxide and water through the process of aerobic respiration in the mitochondria. Fermentation, on the other hand, occurs in the absence of oxygen and involves the partial breakdown of glucose to produce energy in the form of ATP. Therefore, the correct answer is False.

Explanation
Glycolysis is an anaerobic process because it occurs in the absence of oxygen. During glycolysis, glucose is broken down into pyruvate, producing a small amount of ATP and NADH. This process is the first step in both aerobic and anaerobic respiration, but in the absence of oxygen, pyruvate is converted into lactate or ethanol to regenerate NAD+ for the continuation of glycolysis. Therefore, glycolysis is considered an anaerobic process.

Explanation
NAD+ (nicotinamide adenine dinucleotide) can indeed be converted into NADPH (nicotinamide adenine dinucleotide phosphate) through various enzymatic reactions. This conversion is essential for many cellular processes, including the synthesis of fatty acids and cholesterol, as well as the production of energy in the form of ATP. NADPH also plays a crucial role in antioxidant defense mechanisms and in maintaining the balance of reactive oxygen species within cells. Therefore, the statement "NAD+ is turned into NADPH" is true.

Explanation
The given answer options ATP, NADPH, Pyruvate, and Acetyl-CoA are all molecules involved in the breakdown of glucose. ATP is a molecule that provides energy for cellular processes, including the breakdown of glucose. NADPH is a molecule that acts as a reducing agent in metabolic reactions, including the breakdown of glucose. Pyruvate is a product of the initial steps of glucose breakdown, and Acetyl-CoA is a molecule that is further produced from pyruvate and enters the citric acid cycle to generate more ATP. Therefore, all of these molecules are involved in the breakdown of glucose to carbon.

Explanation
Glycolysis is the metabolic pathway that converts glucose into energy. During glycolysis, glucose is broken down into two molecules of pyruvate, producing a net gain of two ATP molecules and two molecules of NADPH. Therefore, the correct answer is ATP and NADPH, as these are the products that result from glycolysis.