What is the mechanism of stomatal opening and closing?

Stomatal opening and closing mechanism.

The ultimate cause of stomatal movement is the expansion of water absorption or water loss and shrinkage of the defending cells. There are currently three theories about the mechanism of stomatal movement:

Under the premise of light, the guard cells carry out photosynthesis, and the CO2 concentration decreases, so that the pH value increases, and at this time, the starch phosphorylase hydrolyzes starch into glucose, resulting in the decrease of the water potential of the guard cells, causing water absorption expansion and stomatal opening. In the dark, respiration produces CO2, pH drops, glucose + phosphate synthesizes starch, water potential rises, cells lose water, and stomata close.

2. Inorganic ions say that under light, the photoactivated H+ pump ATPase decomposes ATP, and while H+ is secreted outside the cell wall, potassium is separated from the human guard cell, resulting in a decrease in water potential, water absorption and expansion of the guard cell, and open stomata.

3. Malic acid production theory Under light, CO2 is consumed, pH rises, and phosphoenolpyruvate produced by glycolysis of starch reacts with HCO3- to form oxaloacetic acid, which is further reduced to malic acid, the water potential of the cell decreases, the water enters the human defense cell, the cell expands, and the stomata open.

The mechanism of stomatal opening and closing of plants is to protect the water loss and water absorption of cells.

When the guard cell loses water, the stomata close, and when the guard cell absorbs water, the stomata open.

Guard cells are cells that are located on both sides of the stomata.

Depending on the light and temperature, the opening and closing of the stomata control photosynthesis and respiration.

When you suck the water, you will open it, and when you put the water on it, it will close.

The opening and closing of the stomata in plants are controlled by guard cells, generally dicots.

The guard cells are mainly semi-penitential crescent-shaped, monocots.

The guard cells resemble a pair of dumbbells. When the air pressure rises, the whole tissue cell becomes a relative curve, and the stomata open when the oval break occurs, and when the turgor pressure drops, the thick wall is tightened, and the stomata are closed.

The opening and closing of the stomata is regulated by guard cells on the leaves, which usually do not have chloroplasts.

But guard cells contain chloroplasts that can use sunlight.

Accomplishes weak photosynthesis.

Together with the rest of the guard cells, it acts as a buffer for the expansion and retraction of mesophyll cells, and is able to regulate the opening and closing of stomata.

On either side of the guard cells are some paraguard tissue cells. Mesophyll cells and surrounding tissue cells, including the presence or absence of paraguard tissue cells, the morphology and number of paraguard tissue cells, etc., can produce various forms, so they can be used as one of the bases for evaluating plant varieties.

The guard cells of dicots are usually half-moon-shaped, while those of monocots resemble a pair of dumbbells. The cell wall of a mesophyll cell.

The thickness is uneven, the half-moon shaped cells connect to the protrusions of the leaf epidermal cells, and the walls are thin and elastic; Close to the concave surface of the hole, the wall is thick and less elastic.

When the turgor pressure increases, the thin wall is flexed and stretched outward, but the wall thickness is rarely stretched, a whole tissue cell is in a relative curved shape, and the oval hole is produced in the middle of the two tissue cells, and the stomata are opened, and when the turgor pressure drops, the histiocytes are closed, and the thick wall is tight, and the stomata are closed.

1. Plant stomata is the main place of transpiration, the main function of plant stomata is to discharge water vapor and carbon dioxide and other substances, water vapor can reduce the temperature of leaves, prevent leaves from being sunburned, discharge carbon dioxide is equivalent to the discharge of waste in the body, and facilitate carbon assimilation and photosynthesis of plants.

2. Stomata is the epithelium opening of plant leaves, stems and other parts, which is a unique structure of plant epidermis, which is generally regulated by the opening and closing of guard cells, and has important significance in plant physiology. The stomata are the main outlet for water vapor to be discharged from the body to the outside of the body during transpiration, and are the channels for the exchange of photosynthesis and external gases between photosynthesis and exhalation.

3. The stomata of most plants are generally opened during the day and closed at night. The opening and closing of the stomata of the plant and the closure of the stomata are controlled by the guard cells, and each opening and closing of the stomata affects the transpiration, photosynthesis, respiration and other functions of the plant.

Summary. Hello, because the chloroplasts inside the guard cell for photosynthesis when illuminated.

With it, the water potential decreases, and the surrounding water flows to guard the cell, gas.

The hole is opened. Conversely, in the dark, the water potential of the guard cells rises.

high, the guard cells lose water, and the stomata are closed.

How light causes the stomata of plant leaves to open.

Hello, because the chloroplasts in the guard cells undergo circular photosynthesis when the light is illuminated, the water potential decreases, the surrounding water flows to the guard cells, and the stomata open. Conversely, under dark conditions, the water potential of the guard cells increases, and the guard cells lose water, and the stomata are closed.

When the light is stronger, the more water is needed for synthesis, so the stomata will be larger.

The stronger the light in a certain range, the larger the stomata will be.

Yes. Is it because the stomata become larger due to strong transpiration due to strong light, or whether the stomata become larger directly due to light.

Who will influence whom first?

Hello, stomata is one of the many small openings in the epithelium of leaves, stems and other plant organs, and is a structure unique to the epidermis of plants. Stomata are usually found in the aerial parts of the plant body, especially on the leaf epidermis, and can also be seen on young stems and flowers, but most submerged plants do not. In a narrow sense, the convex lens-like holes formed between guard cells are often called stomata.

Guard cells differ from epidermal cells in that they contain chloroplasts in their structure, but they are smaller in size and less numerous, and their lamellar structure is underdeveloped, but they can photosynthesize and synthesize carbohydrates. Sometimes it is also accompanied by 2 to 4 paraguard cells adjacent to the guard cells. To include these cells are generalized stomata (stomata or stomatae).

Immediately below the stomata there is a wide intercellular space (air cell). In the metabolism of gases such as carbon assimilation, respiration, and transpiration, stomata become the pathway of air and water vapor, and their passage is regulated by the opening and closing of guard cells, which is of great physiological significance.

The opening and closing of the stomata is controlled by guard cells on the leaf. Normal epidermal cells do not have chloroplasts, but there are chloroplasts in guard cells, which can use sunlight for weak photosynthesis, plus other factors of guard cells, which play a role in regulating the expansion and contraction of guard cells, and can control the opening and closing of stomata.

There are also some paraguard cells on either side of the guard cell. Guard cells and surrounding cells, including the presence or absence of paraguard cells, the shape and number of paraguard cells, etc., can form various types, so they can be used as one of the bases for identifying plant species.

1. Plant stomata is the main place of transpiration, the main function of plant stomata is to discharge water vapor and carbon dioxide and other substances, water vapor can reduce the temperature of leaves, prevent leaves from being sunburned, discharge carbon dioxide is equivalent to the discharge of waste in the body, and facilitate carbon assimilation and photosynthesis of plants.

2. Stomata is the epithelial opening of leaves, stems and other parts of plants, which is a unique structure of plant epidermis, which is generally regulated by the opening and closing of guard cells, which is of great significance in the physiology of plants. Stomata are the main outlet for water vapor from the body to the outside of the body during transpiration, and are the channels for photosynthesis and respiration to exchange with external gases.

3. The stomata of most plants generally open during the day and close at night. The opening and closing of the stomata of the plant is controlled by the guard cells, and the opening and closing of each stomata affects the transpiration, photosynthesis, respiration and other functions of the plant.

The stomata of plants work as follows:

Stomata are the main outlet for water vapor to be discharged from the body to the outside of the body during transpiration, and it is also the channel for photosynthesis and respiration to exchange with external gases, thus affecting transpiration, photosynthesis, respiration and other processes. In general, the stomata open during the day and close at night (except for plants in the family Sedum).

The closure of the stomata is controlled by the guard cells. The different thickness of the cell wall of the guard cells, coupled with the fact that the cellulose microfibrils are attached to the cell wall, can lead to open stomata. When the guard cells absorb water and expand, the thinner outer wall is easy to elongate and expand outward, but the microfibrils are difficult to elongate, so the stomata open and transpiration is strengthened.

The stomata control the entry and exit of carbon dioxide bridges, so they are related to photosynthesis and respiration.

Expand the information of the exhibition.

Exercise factor. Light-induced stomatal movement.

The chloroplasts of the guard cells carry out photosynthesis under light, using CO2, so that the intracellular pH value increases, the starch phosphorylase hydrolyzes starch into glucose phosphate, and the intracellular water potential decreasesThe CO2 produced by respiration in the dark causes the pH value of the guard cells to decrease, and the starch phosphorylase synthesizes glucose into starch, the concentration of cell fluid decreases, the water potential increases, the guard cells lose water, and the stomata close. The osmotic system of guard cells can also be regulated by K.

Photosynthetic photoreaction (cyclic and acyclic photosynthetic phosphorylation) produces ATP, which absorbs K through active transport against the ion concentration difference, reduces the water potential of guard cells, and absorbs water to open the stomata. Note: If the light intensity is below the light compensation point, the stomata are closed;Red light and blue-violet light work best on the light quality that causes the stomata to openSedum plants open their stomata at night to absorb and store CO2 (forming malic acid and storing it in vacuoles), and when the sedum closes, malic acid is decomposed into pyruvate to release CO2 for photosynthesis.

Carbon dioxide affects stomatal movement.

Low concentrations of CO2 promote stomatal opening, while high concentrations of Lily CO2 cause the stomata to close rapidly, regardless of light or darkness. The inhibition mechanism may be that the pH of the guard cells decreases, the water potential rises, and the guard cells lose water, and the stomata open rapidly only after the CO2 is gradually depleted after a period of light exposure.

Temperature affects stomatal movement.

The stomatal opening degree generally increases with the increase of temperature, reaching the maximum at about 30, and the stomata can not be opened well at low temperature (such as below 10) despite long-term light, mainly because the activity of starch phosphorylase is not high, and the temperature is too high will lead to too strong transpiration, and the guard cells lose water and the stomata are closed.