Respiration in Plants

Edited By Team Careers360 | Updated on May 11, 2022 02:59 PM IST

Respiration is the process by which all living organisms, including plants, obtain their energy to sustain themselves. The reactions of respiration produce carbon dioxide and water as by-products, and glucose is required to initiate the reactions.

Respiration in plants: what is it?

Respiration is the process by which cells gain chemical energy by consuming oxygen and releasing carbon dioxide. The respiration of plant cells involves oxygen and a means of discharging carbon dioxide, just like that of animal cells. Since plants do not have specific organs that allow for gas exchange, every part of the plant, including its roots and stems, performs breathing. Respiration and breathing occur through lenticels in hard and woody stems. In all trees, there are tiny pores, known as lenticels, found on the bark.

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As you can see, there are several ways to breathe:

Oxygen + Glucose → Water + Carbon Dioxide with Energy

Therefore, we may conclude from the equation above that respiration causes carbon dioxide to be released and oxygen to be consumed.

Respiration definition Plants

Sugars produced during photosynthesis combined with oxygen are used as energy for plant growth during the respiration process. Photosynthesis and respiration operate in many ways contrary to one another. Through their stomata, plants take in oxygen from the air very much as they do through photosynthesis.

Do plants breathe?

When it comes to planting respiration, this is the most important question. In this sense, plants do not breathe, but rather they respire, as they do not have any specialized organs like lungs. The plant breathes by using lenticels and stomata (found on stems and leaves separately) to carry out gaseous exchanges.

Do plants respire?

This is the most crucial question when it comes to planting respiration. It is generally agreed that plants do not breathe, but rather respire.

Photosynthesis and Respiration

Oxygen and glucose are produced from carbon dioxide and water in the photosynthesis process. Oxygen and glucose are converted into water and carbon dioxide in the cellular respiration process. This process generates by-products such as water and carbon dioxide. ATP is the energy produced by this process.

The role of air temperature:

Plants breathe 24 hours a day, but the night respiration process is more obvious when photosynthesis ends. The temperature should be much cooler at night compared to the daytime because plants can be stressed.

Put yourself in the shoes of a marathon runner. When a runner runs, his/her breathing rate is higher than when they are standing still; this results in an increase in his/her respiration and an increase in body temperature. When plants grow, their respiration is higher than when they are standing still. The respiration rate increases and the temperature increases when the temperature at night rises. Consequently, flowers are damaged and plant growth is impaired.

Anaerobic respiration in plants

Anaerobic respiration (anoxybiotic) occurs when glucose is incompletely broken down in the absence of oxygen to ethanol and carbon dioxide, e.g., in yeast, some bacteria or muscle cells.

A Root's Respiration

The roots are responsible for plant respiration. Soil contains oxygenated air that is already present in the spaces between soil particles. A root hair present on the roots helps absorb oxygen into the roots.

There is direct contact between the root hairs and them. Root hairs are actually lateral tubules that arise from the outer epidermal layers of a root. Plant roots respire through underground spaces.

Air diffuses between soil particles, allowing oxygen to enter root hairs. During respiration, oxygen is transported from root hairs to all parts of the roots. The same root hairs produce carbon dioxide gas during respiration, which is released in the opposite direction from the roots. The roots are thus completed in their respiration process.

Plants are prone to dying if they are watered over for a long period of time. Water exercises all the air between soil particles as a result of too much water. The roots cannot perform aerobic respiration because oxygen is not freely available.

Germinating seeds have a seed coat that prevents oxygen from entering them, so they respire anaerobically during the early stages of germination.

Mangrove trees respire with the help of pneumatophores. A plant's respiration occurs throughout the day and night, resulting in carbon dioxide. However, the amount of carbon dioxide CO2 released during the day is insignificant when compared to the amount of oxygen made by photosynthesis. As a result, sleeping under a tree at night is not recommended.

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The process of respiration stems

The exchange of gases in herbaceous plants takes place through stomata, and the carbon dioxide CO2 that forms during the process is emitted only by the stomata. The exchange of gases occurs through lenticels in plants, which have hard and woody stems. Lenticels are dead cells that form tiny pores on the bark of woody plants and are usually loosely packed.

These ports allow oxygen to pass into the intercellular spaces of cells and carbon dioxide (CO2) to be released into the atmosphere due to diffusion, which completes the process of respiration in stems.

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The rate of transpiration in leaves

Small pores known as stomata provide a pathway for the exchange of respiratory gases in leaves. On the lower side of the leaves, you'll find the stomata in large numbers.

The guard cells at the centre of each stoma seal and regulate the pore in the centre of each stoma. By the method of diffusion, the gas exchange between the atmosphere and the interior of the leaf occurs when the stoma opens, completing the process of respiration in leaves.

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Frequently Asked Questions (FAQs)

1. What is the purpose of giving glucose or fruit juice to dizzy people when a cheese sandwich may provide more energy?

When glucose is absorbed and reaches the bloodstream, it gives instant energy. The digestion and absorption of cheese sandwiches take time. In order to alleviate the patient's immediate need for energy, glucose or fruit juice are given to them.

2. Aerobic respiration produces better results. Explain.

One molecule of glucose can produce up to 36 molecules of ATP in this process. A molecule of glucose is converted to only two molecules of ATP during anaerobic respiration or fermentation, which is less than aerobic respiration. Therefore, aerobic respiration produces more energy.

3. Anaerobic respiration can occur in aerobic conditions in organisms such as humans and angiosperms. How?

The process of aerobic respiration occurs naturally in humans. Heavy exercise, for instance, can cause the muscles to burn more energy (ATP) resulting in a lack of oxygen which causes the muscles to produce lactic acid through anaerobic respiration in order to meet their energetic demands.

4. Explain the term amphibolic pathway for the respiratory pathway.

Acetyl CoA is produced from the degradation of fats and proteins in order to enter the respiratory pathway. In the process of synthesis of fats and proteins, substances are withdrawn from the respiratory pathway and are used for anabolism.

Anabolism is the process of forming substances, while catabolism is the process of breaking them down. Because the respiratory pathway is associated with both catabolism and anabolism, it is referred to as the amphibolic pathway.

5. What is the purpose of mitochondria being called the powerhouse of the cell?

The mitochondria are known as the powerhouse of the cell because they release energy from food molecules with the help of a series of enzyme reactions.

6. What is the "Energy Currency" of a cell?

ATP is sometimes called the "Energy Currency" of the cell.

The organic compound ATP - Adenosine triphosphate, contains phosphate groups, adenine, and sugar ribose. Adenosine triphosphate serves as an energy source for many activities in the body. The molecule is known as the "Currency of the Cell".