Aerobic respiration and anaerobic respiration

I believe that everyone has a certain understanding of the difference between aerobic respiration and anaerobic respiration. This is the way of survival of all things in the world. Aerobic respiration requires the use of oxygen for metabolism, while anaerobic respiration can survive and reproduce in an oxygen-free environment. Anaerobic respiration is mainly for bacterial microorganisms, while aerobic respiration is the main metabolic method of most organisms. Everyone can understand the difference between the two.

Aerobic respiration refers to the process in which cells, with the participation of oxygen and through the catalytic action of enzymes, completely oxidize and decompose organic matter such as sugars, producing carbon dioxide and water while releasing a large amount of energy. Aerobic respiration is the main form of respiration for higher animals and plants. Therefore, respiration usually refers to aerobic respiration. The main site of aerobic respiration in cells is the mitochondria. Generally speaking, glucose is the substance most commonly used by cells during aerobic respiration.

Anaerobic respiration generally refers to the process in which cells, under anaerobic (hypoxic) conditions, break down organic substances such as glucose into incomplete oxidation products through the catalytic action of enzymes, while releasing a small amount of energy. This process is called anaerobic respiration for higher plants, higher animals and humans.

One difference

Anaerobic respiration:

Refers to the incomplete oxidation of organic matter by living cells. This process does not involve molecular oxygen, and the incomplete oxidation products after oxidation are mainly alcohol. Overall reaction equation: C6H12O6→2C2H5OH+2CO2+226 kilojoules (54 kilocalories) In higher plants, anaerobic respiration is often called fermentation. When the incomplete oxidation product is alcohol, it is called alcoholic fermentation; when it is lactic acid, it is called lactic acid fermentation. Under hypoxic conditions, they can only carry out anaerobic respiration to temporarily maintain their life activities. Anaerobic respiration will eventually harm plants, partly because organic matter is incompletely oxidized and produces less energy. Then, due to the Pasteur effect, the rate of glycolysis is accelerated to compensate for the low ATP yield. This in turn will cause the accumulation of incomplete oxidation products, which are toxic to cells; in addition, it will also accelerate the consumption of sugar and there is a risk of exhausting respiratory substrates.

Aerobic respiration:

Aerobic respiration refers to the process in which cells, with the participation of oxygen and through the catalytic action of enzymes, completely oxidize and decompose organic matter such as sugars, producing carbon dioxide and water while releasing a large amount of energy. Aerobic respiration is the main form of respiration in higher animals and plants.

2. Contact

If we analyze the breathing process carefully, we can easily find that the two types of breathing also have something in common.

1. From the perspective of changes in matter and energy, both release energy by decomposing organic matter.

2. From the reaction process point of view, the first step of these two types of respiration is to decompose glucose into pyruvate in the cytoplasm.

3. From the perspective of biological evolution, the atmosphere of the primitive Earth did not contain oxygen. Therefore, the breathing method of organisms at that time was anaerobic respiration. When autotrophic organisms such as cyanobacteria appeared, oxygen appeared in the atmosphere and aerobic respiration appeared. It can be seen that aerobic respiration developed on the basis of anaerobic respiration.

3. Advantages and disadvantages

From the perspective of energy supply, aerobic respiration can release 2870kJ of energy for every mol of glucose broken down. Anaerobic respiration can only release 196.65 kJ of energy when breaking down 1 mol of glucose. For aerobic organisms, most of the energy required for life activities is provided by aerobic respiration. The energy provided by anaerobic respiration cannot meet the needs of maintaining the life activities of organisms. Therefore, aerobic respiration is better than anaerobic respiration in providing energy.