What are the three stages of cellular respiration?

The three stages of aerobic respiration.

a. The first stage:

In the cytoplasmic matrix, one molecule of glucose is broken down into two molecules of pyruvate, and 4 [h] (activated hydrogen) are removed at the same time; During the breakdown of glucose, a small amount of energy is released, and part of the energy is used to synthesize ATP, producing a small amount of ATP. This stage does not require the involvement of oxygen and is carried out in the cytoplasmic matrix. Reactive:

C6H12O6 enzyme 2C3H4O3 (pyruvate) + 4[H]+ a small amount of energy.

2ATP)b, Phase II:

Pyruvate enters the matrix of mitochondria, and the hydrogen in two molecules of pyruvate and 6 water molecules are all removed, and a total of 20 [h] are removed, and acetone is oxidized and decomposed into carbon dioxide; A small amount of energy is released in this process, part of which is used to synthesize ATP, producing a small amount of energy. This stage also does not require the involvement of oxygen and is carried out in the ** stroma. Reactive:

2C3H4O3 (pyruvate) + 6H2O enzyme 20[H]+6CO2 + small amount of energy.

2ATP)c, Phase III:

**On the inner membrane of the chondria, a total of 24 [H] shedding in the first two stages are combined with 6 O2 produced by absorption from the outside world or chloroplast photosynthesis to form water; In this process, a large amount of energy is released, and part of this energy is used to synthesize ATP, producing a large amount of energy. This phase requires the involvement of oxygen and is carried out on the inner membrane of the first chondrium. Reactive:

24[H]+6O2 enzyme 12H2O+ massive energy (34ATP).

h] is a very simplified way of representation. This process is actually the conversion of oxidizing coenzyme (NAD+) to reducing coenzyme (NADH).

Aerobic respiration requires the participation of molecular oxygen, whereas anaerobic respiration does not require the participation of molecular oxygen.

The products of aerobic respiration are carbon dioxide and water, and the products of anaerobic respiration are alcohol or lactic acid.

Aerobic respiration releases more energy, while anaerobic respiration releases less energy. **。

Aerobic respiration: Phase I: CHO2ATP2ATP 4 h (in the cytoplasm).

Phase II: pyruvate 6H o 6Co 20H2ATP (in mitochondrial matrix).

Stage III: 24 h 6o 12h o 34ATP (in the inner mitochondrial membrane).

In the first stage, 1 molar glucose is decomposed into 2 mol pyruvate and 4 mol [H] under the catalysis of enzymes, and a small amount of energy is released (partly lost in the form of heat energy, partly used to synthesize 2ATP) in the cytoplasmic matrix;

In the second stage, 2 moles of pyruvate and 6 moles of water are catalyzed by enzymes to produce 6 moles of carbon dioxide and 20 moles [H], and a small amount of energy is released (partly in the form of heat energy and partly for the synthesis of 2ATP) in the mitochondrial matrix;

In the third stage, 24 moles of oxygen [H and 6 moles of oxygen are catalyzed by enzymes to produce water and release a large amount of energy (partly in the form of heat energy and partly for the synthesis of 34ATP) at the site of the inner mitochondrial membrane.

Anaerobic respiration: Phase I: CH1O2ATP2ATP4H (cytoplasmic matrix).

Phase II: 2 pyruvate 2 alcohol 2CO energy (cytoplasmic matrix) or 2 pyruvate 2 lactate energy (cytoplasmic matrix).

The three stages of cellular respiration are:

Phase I: C6H12O6 2ATP 2ATP 4 h (in the cytoplasm).

Phase II: pyruvate 6H2O 6CO2 20 H2ATP (in mitochondrial matrix).

Stage III: 24 H 6O2 12H2O 34ATP (in the inner mitochondrial membrane).

Application of the principle of aerobic respiration:

1) Crop cultivation should be timely loosened and ventilated, and the aerobic respiration of the root system should be used to promote the absorption of water and inorganic salts; Rice fields need to be drained regularly, otherwise the roots will be toxic to the cells due to anaerobic respiration and produce a large amount of alcohol, causing the roots to rot.

2) One of the reasons for advocating aerobic exercise is not to cause muscle soreness and weakness due to excessive accumulation of lactic acid due to anaerobic respiration of cells due to strenuous exercise.

3) In the process of steamed bread and bread, yeast is used to make the bread steamed bread soft and delicious.

The three stages and equations of cellular respiration are as follows:

Stage 1: Glycolysis (reaction site: cytoplasmic matrix).

1 glucose + 2ADP + 2PI + 2 [NAD] 2 pyruvate + 2 [NADH + H+] + 2ATP

Stage 2: Citric acid cycle (tricarboxylic acid cycle) (site of reaction: mitochondrial matrix).

2 pyruvate + 2 [NAD] + 2 coenzyme A 2 acetyl CoA + 2 [Nadh + H+] + 2CO2

2 acetyl CoA + 6H2O + 6 [NAD] + 2 [FAD] + 2ADP + 2PI 2 Coenzyme A + 6 [Nadh + H+] + 2 FADH2 + 2ATP + 4CO2

Stage 3: Oxidative phosphorylation (electron transport chain) (site of reaction: inner mitochondrial membrane).

28adp+28pi+10【nadh+h+】+2fadh2+6o2→28atp+12h2o+10【nad】+2【fad】

Since glycolysis occurs outside the mitochondria, NADH must enter the mitochondria to be oxidized. Some cells use the equivalent of 2 ATPs to transport NADH into the mitochondria, so that the total amount of ATP produced is 30 instead of 32. But many cells use energy-free methods to transport NADH into the mitochondria, so the total amount of ATP produced is still 32.

So the total amount of ATP produced by a molecule of glucose is generally 30 to 32.

Phase 1: C6H12O6 enzyme 2C3H4O3+4[H]+ a small amount of energy; Phase II: 2C3H4O3 + 6H2O enzyme 20[H]+6CO2 + a small amount of energy; Stage 3:

24[H]+6O2 12H2O+ a lot of energy.

Aerobic respiration phase 1 equation.

In the cytoplasmic matrix, one molecule of glucose is broken down into two molecules of pyruvate, and 4 [h] (activated hydrogen) are removed at the same time; During the breakdown of glucose, a small amount of energy is released, and part of the energy is used to synthesize ATP, producing a small amount of ATP. This stage does not require the involvement of oxygen and is carried out in the cytoplasmic matrix.

Equation: C6H12O6 enzyme 2C3H4O3 (pyruvate) + 4 [H] + small amount of energy (2ATP) (4 [H] is 4NaDH).

Aerobic respiration second stage equation.

Pyruvate enters the matrix of mitochondria, and the hydrogen in two molecules of pyruvate and 6 water molecules are all removed, and a total of 20 [h] are removed, and pyruvate is oxidized and decomposed into carbon dioxide; A small amount of energy is released in this process, part of which is used to synthesize ATP, producing a small amount of energy. This stage also does not require the involvement of oxygen and is carried out in the ** stroma.

Equation: 2C3H4O3 (pyruvate) + 6H2O enzyme 20 [H] + 6 CO2 + small amount of energy (2ATP) (20 [H] is 16 NaDH and Nadph).

Aerobic respiration phase 3 equation.

**On the inner membrane of the chondria, a total of 24 [H] shedding in the first two stages are combined with 6 O2 produced by absorption from the outside world or chloroplast photosynthesis to form water; In this process, a large amount of energy is released, and part of this energy is used to synthesize ATP, producing a large amount of energy. This phase requires the involvement of oxygen and is carried out on the inner membrane of the first chondrium.

The concept is as follows:The so-called "cellular respiration" refers to the series of oxidative decomposition of organic matter in the cell, and finally produces carbon dioxide.

or other products, the process of releasing energy and generating ATP. According to whether aerobic participation is or not, it is divided into aerobic respiration and anaerobic respiration.

The fundamental meaning of cellular respiration is to provide the body with energy that can be used. This is manifested by oxygen consumption and carbon dioxide, water, and adenosine triphosphate.

ATP).

Features of cellular respiration:Enzyme-catalyzed redox reactions in .

2. The energy generated is stored in the high-energy phosphorus acid bond of ATP.

3. The reaction is carried out step by step, and the energy is released gradually.

4. The reaction is carried out in the environment of body temperature, constant pressure, near-neutral pH and water.

The details are as follows:Stage 1: 1 molecule of glucose.

It is divided into 2 molecules of pyruvate.

A small amount of [H] is produced, and a small amount of energy is released, and the rest is lost as thermal energy. This stage does not require the involvement of oxygen and is in the cytoplasmic matrix.

. Stage 2: Pyruvate and water are completely decomposed into carbon dioxide.

Stage 3: The [h] produced by the above two stages goes through a series of chemical reactions.

Significance of cellular respiration:1. Provide direct energy source material - ATP for various life activities of organisms.

2. Provide raw materials for the synthesis of other compounds in the body.

3. Maintain a homeothermic animal.

body temperature. The above content reference: Encyclopedia - aerobic respiration.

The above content reference: Hundred Towns Defeat - Cellular Respiration.

Cellular respiration is mainly aerobic respiration, and aerobic respiration disturbance is divided into three stages:

Stage 1: In the cytoplasmic matrix, one molecule of glucose is decomposed into two molecules of pyruvate, and 4 [H] (activated hydrogen) are removed at the same time; During the breakdown of glucose, a small amount of energy is released, and part of the energy is used to synthesize ATP, producing a small amount of ATP. This stage does not require the involvement of oxygen and is carried out in the cytoplasmic matrix.

Reaction formula: C6H12O6 enzyme 2C3H4O3 (pyruvate) + 4[H] + small amount of energy (2ATP) (4[H] is 4NaDH).

The second stage: pyruvate enters the matrix of mitochondria, and the hydrogen in two molecules of pyruvate and 6 water molecules are all removed, and a total of 20 [h] are removed, and pyruvate is oxidized and decomposed into carbon dioxide; A small amount of energy is released in this process, part of which is used to synthesize ATP, producing a small amount of energy. This stage also does not require the involvement of oxygen and is carried out in the ** stroma.

Reaction formula: 2C3H4O3 (pyruvate) + 6H2O enzyme 20[H]+6CO2+ small amount of energy (2ATP) (20[H] is 16NaDH and Nadph).

Stage 3: On the inner membrane of the chondria, a total of 24 [H] shedding in the first two stages combine with 6 O2 produced by absorption from the outside or chloroplast photosynthesis to form water; In this process, a large amount of energy is released, and part of this energy is used to synthesize ATP, producing a large amount of energy. This phase requires the involvement of oxygen and is carried out on the inner membrane of the first chondrium.

Reaction formula: 24[H]+6O2 enzyme 12H2O+ large amount of energy (34ATP).