Respiration In Plants

All living organisms, including plants, receive their energy required for their survival from a chain of chemical reactions called respiration. The process of respiration requires glucose to start the reactions which are later converted into energy and hence producing carbon dioxide and water as by-products.

Do Plants Breathe?

Yes, plants do require oxygen for respiration which in return give out carbon dioxide. Unlike animals and humans, plants do not have any specialized structures for gaseous exchange but they have stomata (present in leaves) and lenticels (present in stems) which are involved in the exchange of gases. Compared to animals, plant roots, stems, and leaves respire at a very lower rate.

It is important to note here that respiration is not equal to breathing. Breathing is just a part of respiration that takes place in both humans and animals. Plants respire throughout its lifespan as its cells require energy for their survival, but plants do not breathe like humans and animals do.  They breathe through the process called Cellular respiration.

In this process, plants produce glucose molecules through photosynthesis process by capturing the solar energy and converting it into glucose. There are many live experiments to prove that plants do breath. All plants do respire to provide energy for the cells to stay alive.

Let’s have a glance at the process of respiration in plants.

The Process of Respiration in Plants

During respiration, very little amount of gas exchanges takes place within the different parts of the plants. Therefore, each part takes care of its own energy requirements.

Roots, stems, and leaves of plants exchange gases for respiration separately. As we all know, leaves have tiny pores called as stomata, which is used for the exchange of gases. The oxygen, taken in through stomata is used by cells in the leaves to break down glucose into carbon dioxide and water.

Respiration in Plants

Respiration In Roots

Roots also absorb air from the air spaces present between the soil particles. Thus, the oxygen absorbed through roots are used to release energy which is later utilized for the transportation of minerals and salts from the soil.

Respiration in Roots

We are aware of the fact that plants have the unique ability to photosynthesize. Photosynthesis is the process by which plants prepare their own food. It takes place only in the parts of plants that contain chlorophyll, i.e. only in the green parts of the plants. The process of photosynthesis is so prominent that it sometimes masks the process of respiration in plants. However, we must know that respiration in plants occurs throughout the day while photosynthesis takes place only in the presence of light. Therefore, at night the respiration in plants becomes prominent. That is why we often hear that people are asked not to sleep under a tree at night. This may cause suffocation due to the excessive presence of carbon dioxide released by trees as a result of respiration.

Respiration In Stems

Respiration In Stems- Lenticels

In the case of the stem, the air gets diffused in the stomata and passes through various parts of the cell for respiration. The carbon dioxide produced during this stage also diffuses through the stomata. In higher plants or woody plants, the gaseous exchange is carried out by lenticels.

Respiration In Leaves

Respiration In Leaves - Opening and Closing the Stomata

Leaves comprise of tiny pores referred to as stomata. The exchange of gases takes place via stomata through the process of diffusion. Each stoma is controlled by Guard Cells. The opening and closing of the stoma help in the exchange of gases between the atmosphere and the interior of Leaves.

Differences between Respiration and Photosynthesis

Photosynthesis   Respiration
This process is common to all green plants containing chlorophyll pigments. This process is common to all living things including plants, animals, birds, etc.
It synthesizes foods. It oxidizes foods.
It stores energy. It releases energy.
Photosynthesis is an anabolic process. Respiration is a catabolic process.
It requires cytochrome. It also requires cytochrome.
Endothermal process. Exothermal process.
It is comprised of products like sugar, oxygen, and water as products. It is comprised of products like hydrogen and carbon-dioxide.
During Photosynthesis, radiant energy is converted into potential energy. During Respiration, potential energy is converted into kinetic energy.
It takes place only in the presence of sunlight. It takes place continuously throughout the life process from birth to death.

Types of Respiration

There are two main types of respiration. 

Aerobic RespirationAerobic Respiration

This type of respiration occurs within the mitochondria of all eukaryotic organisms. In this process, food molecules are completely oxidized into the water, carbon-dioxide and energy are released in the presence of oxygen. All higher organisms respire aerobically and this process requires atmospheric oxygen.

Anaerobic Respiration

This type of respiration occurs within the cytoplasm of prokaryotic organisms like bacteria and yeast. In this process, less energy is released due to the incomplete oxidation of food in the absence of oxygen. Carbon dioxide and Ethyl alcohol are produced during anaerobic respiration.

Stay tuned with BYJU’S to learn more about Respiration in Plants.

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If you suddenly run a lot, you experience cramps in the leg muscles. Can you think of the reason behind it?