Question

In glycolysis, as in all the stages of cellular respiration, the transfer of electrons from electron donors to electron acceptors plays a critical role in the overall conversion of the energy in foods to energy in ATP. These reactions involving electron transfers are known as oxidation-reduction, or redox, reactions.

1. When a compound donates (loses) electrons, that compound becomes ___________. Such a compound is often referred to as an electron donor.
2. When a compound accepts (gains) electrons, that compound becomes ___________ . Such a compound is often referred to as an electron acceptor.
3. In glycolysis, the carbon-containing compound that functions as the electron donor is ___________.
4. Once the electron donor in glycolysis gives up its electrons, it is oxidized to a compound called ____________.
5. ____________ is the compound that functions as the electron acceptor in glycolysis.
6. The reduced form of the electron acceptor in glycolysis is _________.

Answer 1

During glycolysis in cellular respiration, glucose acts as the electron donor and becomes oxidized to pyruvate. NAD+ serves as the electron acceptor and becomes reduced to NADH.

Step-by-step explanation:

In glycolysis and other stages of cellular respiration, the transfer of electrons between molecules is a crucial part of the energy conversion process. These electron transfer reactions are known as oxidation-reduction, or redox, reactions.

1. When a compound donates (loses) electrons, that compound becomes oxidized. Such a compound is referred to as an electron donor.
2. When a compound accepts (gains) electrons, it becomes reduced. This compound is referred to as an electron acceptor.
3. In glycolysis, the carbon-containing compound that functions as the electron donor is glucose.
4. Once the electron donor in glycolysis gives up its electrons, it is oxidized to a compound called pyruvate.
5. NAD+ is the compound that functions as the electron acceptor in glycolysis.
6. The reduced form of the electron acceptor in glycolysis is NADH.

Answer 2

1. Oxidized

2. Reduced

3. Glucose

4. Pyruvate

5. NAD⁺

6. NADH

Step-by-step explanation:

When a substances looses electron, looses hydrogen or gains oxygen then the substance is said to be oxidized.

But, for reduction reverse happens i.e. when a substance gains electrons, gains hydrogen or looses oxygen, then it is said to be reduced.

Also, the substance which itself gets reduced and oxidizes other substance is known as oxidizing agent. Redox reactions occur simultaneously i.e. when one substance gets oxidized then only another substance will get reduced.

During glycolysis, glucose (C₆H₁₂O₆) which is a 6 carbon compound looses electrons to ultimately get converted into a 3 carbon compound known as pyruvate (CH₃COCOOH). During this process, an oxidizing agent known as NAD⁺ accepts the electron and itself gets reduced to become NADH.

The chemical formula of glucose is C₆H₁₂O₆ while the chemical formula of pyruvate is CH₃COCOOH. If we will look at their chemical formulas we can easily detect that glucose has lost hydrogen as compared to pyruvate that means glucose has got oxidized. In glucose, there are 12 hydrogen atoms against 6 carbon while in pyruvate there are only 4 hydrogen atoms against 3 carbon atoms so it simply means glucose has been oxidized in the process because in resultant molecule which is pyruvate there are comparatively less hydrogen atoms.