Application of photosynthesis principle In the middle of winter, in order to increase the yield of cucumber, a melon farmer placed three big briquette furnaces in the winter warm greenhouse, so as to increase the temperature and carbon dioxide concentration in the greenhouse, so that the cucumber could be put on the market as soon as possible, It's right to think the opposite way. Do you think it's scientific for the melon farmer to do so? Where will you stand? Try to explain the reason

Application of photosynthesis principle In the middle of winter, in order to increase the yield of cucumber, a melon farmer placed three big briquette furnaces in the winter warm greenhouse, so as to increase the temperature and carbon dioxide concentration in the greenhouse, so that the cucumber could be put on the market as soon as possible, It's right to think the opposite way. Do you think it's scientific for the melon farmer to do so? Where will you stand? Try to explain the reason

I think the practice of melon farmers has a certain truth: in the daytime, three coal briquette furnaces are burning, which can not only raise the temperature, but also increase the CO2 concentration in the greenhouse, which will help to improve the photosynthetic rate. In the evening, burning two coal briquette furnaces can make the temperature in the greenhouse not too high, and appropriately reduce the cost of respiration on the consumption of organic matter

What is the principle of plant photosynthesis

Photosynthesis can be divided into two stages: light reaction and carbon reaction
2.1 photoreaction
Conditions: light, photosynthetic pigment, photoreactive enzyme
Setting: thylakoid membrane of chloroplast
The discovery of photosynthesis:
Water (raw material) + carbon dioxide (raw material) light (condition) & chloroplast (site) = oxygen (product) + organic matter (product)
① (2) ATP synthesis: ADP + PI + energy → ATP (catalyzed by light, enzyme and chloroplast pigment)
Influencing factors: light intensity, CO2 concentration, water supply, temperature, pH, mineral elements, etc
Significance: ① photolysis of water to produce oxygen. ② conversion of light energy into chemical energy to produce ATP to provide energy for carbon reaction. ③ synthesis of NADPH (reduced coenzyme II) from hydrogen ion, a product of photolysis of water, to provide reducing agent for carbon reaction. NADPH (reduced coenzyme II) can also provide energy for carbon reaction
The detailed process is as follows:
The system is composed of a variety of pigments, such as chlorophyll a, chlorophyll b, carotenoids and so on. It not only broadens the spectrum of photosynthesis, but also other pigments can absorb excessive strong light to produce the so-called photoprotection. In this system, when photons hit the pigment molecules in the system, it will be as shown in the picture, There are two kinds of reaction centers. The absorption spectrum of the light system reaches the peak at 700 nm, and the peak at 680 nm in the second system. The reaction center is composed of chlorophyll a and specific protein (chlorophyll a here is due to its special position rather than structure), The type of protein determines the absorption wavelength of the reaction center. After the reaction center absorbs the light of a specific wavelength, chlorophyll a excites an electron, and the nearby enzyme breaks the water into hydrogen ions and oxygen atoms, and the excess electrons make up for the deficiency of chlorophyll a. then chlorophyll a produces ATP and NADPH (reducing coenzyme) molecules through the process shown in the figure, The process is called electron transport chain
2.2 carbon reaction
The essence of carbon reaction is a series of enzymatic reactions. It was originally called dark reaction. Later, with the deepening of research, scientists found that this concept is not accurate. Because the so-called dark reaction can only be carried out in the dark for a very short time, and can be continuously carried out under the condition of light, and regulated by light, Scientists engaged in plant physiology agreed to change the dark reaction to carbon reaction
Conditions: carbon reaction enzyme
Setting: chloroplast matrix
Influencing factors: temperature, CO2 concentration, pH, etc
The process of dark reaction is different in different plants, and the anatomical structure of leaves is also different. This is the result of the adaptation of plants to the environment. Dark reaction can be divided into three types: C3, C4 and cam. The three types are divided according to the different processes of carbon dioxide fixation. For the most common type of C3 reaction, plants inhale carbon dioxide from the outside into cells through stomata, Chloroplast contains C5, which can fix CO2 to C3. C3 reacts with NADPH under the condition of ATP energy supply to form carbohydrate (CH2O) and reduce C5. The reduced C5 continues to participate in the dark reaction
The essence of photosynthesis is to change CO2 and H2O into organic matter (material change) and light energy into active chemical energy in ATP, and then into stable chemical energy in organic matter (energy change)
CO2 + H2O (light, enzyme, chloroplast) = (CH2O) + O2
(CH2O) denotes carbohydrate