What is the reason for the increase in carbon dioxide in the exhaled breath of a person?

Red blood cells exchange carbon dioxide produced by metabolism with inhaled oxygen in the alveoli, so carbon dioxide increases.

Aerobic respiration refers to the process in which cells completely oxidize and decompose organic substances such as sugars through the catalytic action of enzymes with the participation of oxygen, producing carbon dioxide and water, and releasing a large amount of energy at the same time.

Aerobic respiration is the main form of respiration in higher animals and plants, so what is commonly referred to as respiration refers to aerobic respiration. The main site where cells undergo aerobic respiration is mitochondria. In general, glucose is the substance most commonly used by cells for aerobic respiration.

The whole process of aerobic respiration can be divided into three stages: in the first stage, one molecule of glucose is broken down into two molecules of pyruvate, and a small amount of hydrogen (denoted by [h]) is produced in the process of decomposition, and a small amount of energy is released at the same time. This stage is carried out in the cytoplasmic matrix; In the second stage, pyruvate undergoes a series of reactions to break down into carbon dioxide and hydrogen, while releasing a small amount of energy.

This stage is carried out in the ** chondria ; In the third stage, the hydrogen produced in the first two stages, after a series of reactions, combines with oxygen to form water, and at the same time releases a large amount of energy. This stage is also carried out in the ** granula. Each of the above three chemical reactions is catalyzed by different enzymes.

In the organism, 1mol of glucose is completely oxidized and decomposed, and a total of 2870kJ of energy is released, of which about 1161kJ of energy is stored in ATP, and the rest of the energy is lost in the form of heat energy.

When people inhale air, they inhale oxygen, oxygen combines with hemoglobin, supplies oxygen to cells, and produces carbon dioxide after cellular respiration, which will return to hemoglobin, and when it passes through the lungs, carbon dioxide is separated, so carbon dioxide increases in the air exhaled by people. (Pick me).

That's because it absorbs oxygen and circulates it, which eventually produces carbon dioxide, which is then excreted from the body.

Human cells undergo aerobic respiration to consume oxygen and turn it into carbon dioxide, and the equation is in high school biology textbooks.

c6h12o6+12 o2 --6co2+ 6h2o+atp

In terms of the proportion of breath exhaled by people, there is still more oxygen than carbon dioxide.

The normal air content is about 79% nitrogen

Oxygen is about 21%, carbon dioxide is about.

After human respiration, gas exchange occurs at the alveoli (using the diffusion of dust and migratory gases), and the carbon dioxide content increases a little, while the oxygen content decreases a little!

About 79% of the exhaled breath is nitrogen

Oxygen is about 16%.

Carbon dioxide is about 4%.

It can now be seen that the oxygen emission in the exhaled air is 5 percentage points lower than that of the inhaled air, but it is still 12 percentage points higher than the carbon dioxide (which has increased by almost 4 percentage points).

According to the Encyclopedia, the exhaled air content accounts for 74% of nitrogen, 16% of oxygen, 6% of water vapor, and 4% of carbon dioxide. (Average).

Carbon dioxide, a carbon oxide, with the chemical formula CO2 and the chemical formula, is a colorless and odorless or colorless and odorless gas with a slightly sour aqueous solution at room temperature and pressure, and is also a common greenhouse gas, or a component of the air (accounting for the total volume of the atmosphere.

Carbon dioxide is widely present in nature, although the amount is small, but it has a significant impact on the earth's surface temperature, plant photosynthesis, etc., and is closely related to human survival. In the air inhaled by the human body, carbon dioxide accounts for only 004 percent of the volume; But in the exhaled breath, carbon dioxide is the main thing. So, how is such a large amount of carbon dioxide produced in the human body?

Many people may think that the lungs are the main place where carbon dioxide is produced, which is wrong. Although the lungs are an important place for gas exchange, the factories that produce carbon dioxide are cells, and the carbon dioxide exchanged by the lungs is produced by tissue cells and transported to the lungs with the bloodstream. In daily life, starch, fat and protein, the three major nutrients that maintain the body's material metabolism and provide energy, are all carbohydrates, and the molecular structure contains carbon-hydrogen bonds, and energy is stored in them.

In the process of metabolism, tissue cells use the inhaled oxygen to oxidize and decompose the three major substances, break the carbon-hydrogen bonds, and release energy; At the same time, hydrogen is oxidized into water and carbon is oxidized into carbon dioxide, which is the mechanism of carbon dioxide production in the body. Once carbon dioxide is produced, cells rush it into the bloodstream, where red blood cells carry it to the lungs and excrete it through exhalation.

The reason for the abundance of oxygen is that only a small part of the oxygen is exchanged when the gas is exchanged in the lungs, and the carbon dioxide in the blood diffuses into the lungs, making the carbon dioxide significantly more, but the total amount of carbon dioxide is still less than that of oxygen.

In the air, carbon dioxide accounts for about 21% and oxygen accounts for about 21%.

There is a certain limit to the amount of dissolved oxygen in the blood, and after the oxygen enters the lungs with the air, only a part of the substances can be exchanged and turned into carbon dioxide.

If part of the oxygen enters the blood, it will lose its metabolic ability due to peroxygen, so the exhaled gas composition is still oxygen and carbon dioxide. Zi Xinwei.