What is Stomata? – Definition, Structure, Types

Stomata is a very essential part of a plant, as it helps in various important processes like Photosynthesis, and the exchange of carbon dioxide and oxygen. Students who study Biology come across this topic sooner or later as part of their academics. To help them, we have provided a detailed guide about the basics and structure of stomata, along with functions, and other important aspects of academic relevance. We would also explain different types of stomata and uses of stomata from different perspectives.

What is Stomata?

As stated in the above section, stomata is defined as tiny openings that are located on the epidermis of leaves. These openings operate on their own, opening and closing. Besides, this method, directly controls the transpiration rate, as it also plays an important role in photosynthesis, as well as in the exchange of carbon dioxide and oxygen.  The tiny pores of stomata can be clearly seen in microscope, and a single pore is called Stoma. While these are generally located only in the epidermis of leaves, in a certain structure of stomata, they can also be seen in the others parts of a plant, especially the stem.

Structure of Stomata

Here in this section, we will talk about the structure of Stomata in great detail, and explain the different components in the Stomata structure.  

As you can see from the above picture, there are multiple components in a Stomata such as Vacuole, Guard Cells, Stomatal Pore, Nucleus, Inner Thick Wall, Chloroplast, Outer Thin Wall, etc. All these components play an important role in the process of transpiration, as thick stomata walls open and close, to absorb carbon dioxide in the air, and release oxygen into the atmosphere.  

• Epidermal Cell: This is the outermost layer of a plant and is composed of cells that are born out of dermal tissues. These cells generally look irregular in their shape and play a key mechanical support to the plant
• Subsidiary Cell: The subsidiary cell can be seen next to the guard cells in the stroma of a leaf. These cells are in the proximity of mother cells and also provide support
• Stomatal Pores: These are the minute pores seen under a leaf’s surface. These openings extend a crucial function in gas exchange in a plant, most commonly oxygen and carbon dioxide.
• Guard Cells: Guard cells are kidney-shaped or at times seen in the form of dumbbells, and function to ensure the stoma’s opening and closing mechanism is proper.

Types of Stomata

Now that you have understood the Stomata in leaves, their functions, structure, etc. Let us now talk about the different types of Stomata briefly here in this section.  

• Diacytic Stomata – The stomata is surrounded by subsidiary cells, which are placed perpendicular to the guard cells in the stomata. 
• Anomocytic Stomata – Unlike other stomata, these have a fixed shape and size, and are embedded in epidermal cells. However, it is very hard to find the number of anomocytic cells, or their arrangement generally. 
• Paracytic Stomata – This stomata observes two subsidiaries that surround the stomatal pore parallelly, as well as the guard cell. 
• Gramineous Stomata – Similar to the paracytic cell, the subsidiary cells are placed parallel to the guard cells. More importantly, in these types of stomata, each single stomata consists of two guard cells, which are in a shape similar to that of dumbbells. 
• Anisocytic Stomata – This stomata are generally surrounded by three subsidiary cells, each of different sizes.  

Functions of Stomata

The Stomata generally have various different functions, which we will explain in detail below. 

• From the above description, as you can understand, the uses of Stomata can be multiple and diverse too. Stomata play a very important role in the process of Photosynthesis, which generally involves, the release of oxygen and the uptake of carbon dioxide. This among stomata functions is the most crucial one for the survival and health of a plant.
• Another important uses of stomata is that it is essential for maintaining the moisture balance, based on the changes in weather.
• As per other stomata functions, they perfectly in helping remove the excess water in the plants through the openings.
• The gaseous exchange also takes place with the help of stomata, which ensures that all the required gases are available for the plant to boost its growth.
• Furthermore, as per the uses of stomata and we will realize that, sometimes, the water present in the plants escapes through the pores, which is why stomatal closure at night is important. This dimension of is among the crucial stomata functions.

Conclusion

In the above article, we have talked about the Stomata in leaves, and stomata in plants in great detail, along with a detailed description of its structure’s components, functions, and types. Besides, there are many other complex topics like this, in the vast syllabus of Biology subject. Thus, if you have any doubts regarding any topics, or if you are struggling with any other subjects like Physics and Chemistry, then it would be a good idea for you to join the Online Interactive Classes offered by the Tutoroot platform. 

Frequently Asked Questions

Where is the stomata located? 

Stomata is found in various parts of the plant such as leaves, stems, flowers, and roots. 

State the function of stomata? 

The Stomata has various different functions as mentioned above exchanging gases, photosynthesis, releasing oxygen or absorbing carbon dioxide, and many more. 

What are various stomata functions?

The functions of stomata are,

• Stomata play a very important role in the process of Photosynthesis, which generally involves, the release of oxygen and the uptake of carbon dioxide. This among stomata functions is the most crucial one for the survival and health of a plant.
• Another important use of stomata is that it is essential for maintaining the moisture balance, based on the changes in weather.
• As per other stomata functions, they perfectly help remove the excess water in the plants through the openings.
• The gaseous exchange also takes place with the help of stomata, which ensures that all the required gases are available for the plant to boost its growth.
• Furthermore, as per the uses of stomata, we will realize that, sometimes, the water present in the plants escapes through the pores, which is why stomatal closure at night is important. This dimension is among the crucial stomata functions.

What are the types of stomata?

Here are the types of stomata,

• Diacytic Stomata – The stomata is surrounded by subsidiary cells, which are placed perpendicular to the guard cells in the stomata.
• Anomocytic Stomata – Unlike other stomata, these have a fixed shape and size, and are embedded in epidermal cells. However, it is very hard to find the number of anomocytic cells, or their arrangement generally.
• Paracytic Stomata – These stomata observe two subsidiaries that surround the stomatal pore parallelly, as well as the guard cell.
• Gramineous Stomata – Similar to the paracytic cell, the subsidiary cells are placed parallel to the guard cells. More importantly, in these types of stomata, each single stomata consists of two guard cells, which are in a shape similar to that of dumbbells.
• Anisocytic Stomata – These stomata are generally surrounded by three subsidiary cells, each of different sizes.