Question

What is the goal of aerobic cellular respiration?

Answer 1

Aerobic respiration:

1. Aerobic respiration is the process of cellular respiration that takes place in the presence of oxygen gas to produce energy from food.
2. This type of respiration is common in most plants and animals, birds, humans, and other mammals.
3. Aerobic cellular respiration occurs in the cytoplasm and mitochondria.
4. Complete oxidation of glucose during aerobic respiration results in the formation of 38 ATPs and CO₂ and water is released.

Cellular respiration:

1. There are three combined pathways that are required to form cellular respiration. These pathways are glycolysis, the Krebs cycle, and the oxidative phosphorylation pathway.
2. Among them, glycolysis and the Krebs cycle are necessary for the breakdown of food molecules, while the third pathway, i.e. oxidative phosphorylation, converts energy from food molecules into ATP.
3. Glycolysis occurs in the cytoplasm of the cell. In this process, cells break down glucose into pyruvate.
4. Pyruvate is a compound containing three carbon atoms.
5. After this step, pyruvate is broken down into a two-carbon molecule called acetyl-coenzyme A (acetyl-coA) and carbon dioxide C02).
6. The cell uses this acetyl-CoA and enters the Krebs cycle.
7. This step occurs in the mitochondrial matrix.
8. In this step, acetyl-CoA breaks down into carbon dioxide.
9. During oxidative phosphorylation, there is a transfer of energy from the cell due to the breakdown of food into ATP molecules.
10. Oxidative phosphorylation takes place in the inner membrane, also known as the mitochondrial ridges.

In the first step, energy is obtained by substrate-level phosphorylation via glycolysis, and this step is followed by three steps that perform aerobic respiration by oxidizing the end product of the process. fecal sugar.

First step: Glycolysis:

1. Glycolysis is the first step in the process of extracting energy from glucose. Glycolysis is a biochemical pathway with 10 reactions.
2. The site of glycolysis is the cytoplasm of the cell because the enzymes required for glycolysis are present in the cytoplasm.
3. They are not associated with any membranes or organelles.
4. In this reaction, two ATP molecules are used in the initial steps.
5. However, at the end of the cycle, four ATP molecules are formed by substrate-level phosphorylation.
6. Therefore, there is a net yield of 2 ATP while catalyzing a glucose molecule by glycolysis.
7. In addition, four electrons are captured during NADH formation and can be used for ATP production through aerobic respiration.
8. Furthermore, by this reaction, two pyruvate molecules are formed that still contain most of the energy present in the original glucose molecule.
9. This stage occurs in both aerobic and anaerobic respiration.

Second Stage: Pyruvate Oxidation:

1. This phase starts with the final product from the first stage.
2. This step involves converting pyruvate to carbon dioxide, as well as a two-carbon molecule known as acetyl-CoA.
3. The conversion of each molecule of pyruvate results in the reduction of one molecule of NAD+ to NADH.
4. This NADH can also be used to produce ATP.
5. Therefore, at this step, there are 2 NADH molecules.

Third Stage: Krebs Cycle:

1. Acetyl-coA enters the Krebs cycle.
2. This cycle is made up of nine different reactions known as the Krebs cycle.
3. This cycle is named after the British biochemist, Sir Hans Krebs.
4. This cycle is also known as the citric acid cycle because, in the early stages of this cycle, citric acid or citrate is formed.
5. It is also known as the tricarboxylic acid cycle because citrate has three carboxyl groups.
6. In the Krebs cycle, two more ATP molecules are extracted by substrate-level phosphorylation.
7. Furthermore, a large number of electrons are removed and can be used to reduce NAD+ and it is converted to NADH useful for ATP production by the electron transport chain.