Stomatal types and representative plants, plant stomatal types

Stomata, one of the many small openings in the epithelium of leaves, stems and other plant organs, are structures unique to the epidermis of plants. Stomata are usually found in the aerial parts of plants, especially on the leaf epidermis, and can also be seen on young stems and petals, but most submerged plants do not.

Sedum succulents have two sets of stomata that alternate day and night breathing, so these succulents can make oxygen without photosynthesis.

Plant stomata are a special organ in the plant body, which appears in roots, stems, leaves, flowers and other parts, and is a channel for plants to breathe, emit carbon dioxide, and absorb water and nutrients. There are two types of plant stomata: normally open stomata and controlled stomata.

The normally open stomata can be said to be the window of plant life, through which the continuous evaporation of water helps the plant to exchange substances in the plant body. The normally open stomata of some plants have some special morphologies and structures, such as the tiny stomata of desert plants such as goosefoot firewood, and the linear stomata of Masson pine. The presence of these stomata helps these plants to survive in a dry environment and maintain the water balance in the plant.

The controllable stomata are manifested in the fact that when the environmental conditions deteriorate, the plant can protect itself by controlling the switch of the stomata . In other words, these pores are usually able to open or close actively due to environmental factors such as light, temperature, air quality, etc. The most common stomata in plants is the "cantilever stomatal opening" based on carbon dioxide levels, i.e. the stomata are opened to absorb enough carbon dioxide.

In addition, there is a "stomatal opening method controlled from the outside in", that is, the opening and closing of the stomata is regulated by endogenous substances such as palmitoyl-CoA produced by resin branching secretions or cell membranes.

In general, plant stomata are a very important organ, which is responsible for the circulation of water, carbon dioxide and other substances in the plant body and the function of maintaining the water balance in the plant body. Understanding the different types of stomata in Ruzhou can help us better understand the mechanism of plant life activities and provide a scientific basis for environmental protection. <>

There are many stomata in the lower epidermis of the leaves, less stomata in the upper epidermis, and the upper epidermis receives sunlight, and the number of stomata is small, which can reduce water evaporation. Water lilies are floating plants, and the stomata are distributed in the upper epidermis for gas exchange.

The stomata are ventilated structures on the epidermis, and the pores are ventilated structures on the peridermis.

1. Irregular four-celled type: 4 paraguard cells irregularly surround the guard cells in various ways.

2. Polar cell type: many parts of the guard cell are surrounded by a "U" type paraguard cell, and only one pole is surrounded by a single epidermal cell.

3. Common circumferential cell type: there is a crescent-shaped paraguard cell outside the guard cell, and there is also a paraguard cell surrounded by this paraguard cell, and the vertical periphery wall of the two paraguard cells is connected together towards the distal axis.

4. Horizontal type: 2 paraguard cells surround the guard cells in a ring.

5. Polyaxillary cell type: 1 paraguard cell almost surrounds 2 guard cells, and this paraguard cell is surrounded by another crescent-shaped cell.

There are four types of stomata in dicots:

Irregular, paraguard cells with no special morphological differentiation around guard cells;

Unequal, the guard cells are surrounded by three paraguard cells;

Parallel, with several paraguard cells parallel to their long axis on the outer surface of the guard cell;

In the transverse type, a pair of paraguard cells are at right angles to the long axis of the guard cells. There are also differences in the morphology of guard cells surrounding the stomatal space, and the guard cells of most plants are kidney-shaped, with a wall thickness near the stomatal space and a thin wall in the dorsal stomatal space.

The guard cells of monocots such as rice and wheat are dumbbell-shaped, with thick walls in the middle part and thin walls at both ends.

The stomata are the gateways for gas exchange between the plant body and the external environment.

The stomata are cavities surrounded by a pair of half-moon-shaped guard cells, and its wonder is that it can open and close automatically, and the opening and closing of the stomata are controlled by the guard cells. When the plant undergoes transpiration, the water in the leaves absorbs heat and becomes water vapor, which is lost to the outside air through the stomata.

The stomata are cavities surrounded by guard cells that are born in pairs and opposites, and the guard cells are half-moon-shaped and contain chloroplasts. Therefore, the stomata are the "gateway" for the transpiration and water loss of the plant body, and the entry and exit of oxygen and carbon dioxide also pass through the stomata during photosynthesis and respiration, so the stomata are also the "window" for the gas exchange between the plant body and the outside world.

At night, plants mainly carry out respiration and transpiration, and the gas that enters the leaves of the plant body from the leaf stomata is mainly oxygen, and the gas that is lost from the leaf stomata to the atmosphere is water vapor.

Stomata are many small openings in the epithelium of leaves, stems and other plant organs. It is a structure unique to the skin 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 petals, 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. It is also sometimes accompanied by 2-4 paraguard cells adjacent to the guard cells.

The inclusion of these cells is a generalized stomata (or stomatal apparatus).

Summary. Most plants have two types of stomatal shafts, respectively"Length type"with"Width type"。The length type stomatal shaft is used to control the opening and closing of the pores, while the width type stomatal shafts are used to control the size of the pores.

Some plants have only one type of stomatal axis, and this is usually because they have special adaptability, and one plant has only one type of stomatal axis.

Most plants have two types of stomatal shafts, respectively"Length type"with"Width type"。The length type stomatal shaft is used to control the opening and closing of the pores, while the wide slag type stomatal shaft is used to control the size of the stomata containing the elder brother. Some plants have only one type of stomatal axis, often because they have special adaptations, such as plants growing in arid environments that can reduce water evaporation while still having gas exchange.

Plants with a single type of stomatal axis may be specialized, growing and propagating under specific environmental conditions. <>

Problem solving ideas: Stomata usually exist in the aboveground parts of the plant body, especially on the leaf epidermis, generally more in the lower leaf epidermis, and can also be seen on young stems and petals

Because the upper epidermis directly receives sunlight and the temperature is relatively higher than that of the lower epidermis, the water in the leaves is relatively easy to be lost from the stomata of the upper epidermis The stomata serve as the gateway for transpiration of water in and out, if the water evaporates too much, especially in the hot summer, it will make the plant wilt and even die, so the stomata of the lower epidermis will avoid the occurrence of this phenomenon The stomata on the leaves of plants are mainly distributed in the lower epidermis of the leaves.

Therefore, b,1, the stomata on the leaves of plants are mainly distributed in ( )aThe upper epidermis of the leaves.

b.The lower epidermis of the leaves.

c.On the veins of the leaves.

d.mesophyll.