Why Air Is Called the Breath of Life in Biology
Do you know why it becomes very difficult for us to breathe as we go to higher altitudes? It is because as we go to higher altitude, air pressure gets very less, and as a result, the amount of oxygen is reduced, and we start feeling altitude sickness. Do you know the composition of air? Which gas is present in a larger amount of air?
Air is a mixture of various gases. Nitrogen is present in large amounts of air, and some gases, such as helium and argon, are present in very few amounts.
What is Air?
Air is a mixture of various gases such as nitrogen, oxygen, other gases, water vapours, and dust particles. It is colourless and odourless. The movement of air from a high-pressure zone to a low-pressure zone is called wind.
Composition of Air
Air is a mixture of many gases. The percentage of these gases also varies. Percentages of gases present in the air are given below:
Nitrogen - 78% of air is made of nitrogen gas.
Oxygen - 21% of air made of oxygen.
Other gases - 1% of other gases made air. Other gases include carbon dioxide, argon, etc.
Importance of Air
Air has many importances. Some of the importance is given below:
Air helps maintain the temperature of the earth by circulating the hot and cold air.
The water cycle also maintain by the circulation of air.
Moving air also helps in the locomotion and flight of insects and birds.
Nitrogen gas is used by plants to make amino acids and proteins.
Seeds dispersed from one place to another place with the help of air.
Oxygen is inhaled from the air while breathing.
The ozone layer protects animals and plants from ultraviolet radiation.
Air is the most important element for sustaining life on earth.
Role of Air in Human Life
Oxygen is the most important gas for the survival of human beings, it assists in respiration, and oxygen helps in the combustion of food, from which ATP is released.
Ozone protects us from harmful radiation.
Air Pollution and Its Side Effects
Air pollution is defined as undesirable changes in the quality of air. It may be a physical, chemical, and biological change in the air quality.
There are various bad impacts of air pollution on human health.
It causes acid rain, which can damage monuments, plants, and animals.
It can also deplete the ozone layer, which leads to the entry of harmful ultraviolet radiation and cause various types of diseases in humans, such as cancer or skin diseases.
If the carbon monoxide level is high in the air, it can cause various harm to live organisms. It is a highly poisonous gas that binds to haemoglobin and reduces the oxygen-carrying capacity of the haemoglobin molecule.
It can cause various respiratory diseases such as asthma, shortness of breath.
It can also damage plants, and their chlorophyll.
Interesting Facts
Our lungs can hold up to seven litres of air.
Most oxygen in our atmosphere is obtained from oceans and seas.
Beijing cough is a disease in China caused due to increased pollution.
More than 65% of deaths in Asia caused due to air pollution.
Almost 80% of respiratory diseases occur due to air pollution.
Pollen grains of flowers can also contribute to air pollution.
Important Questions
Q1. Who discovered oxygen?
Ans: Oxygen was discovered by Joseph Priestley in 1774. It is used for breathing and is responsible for the burning of substances.
Q2. What gases do we inhale and exhale?
Ans: We inhale oxygen and exhale carbon dioxide while breathing. Air contains 21% oxygen, and less than 0.03% of carbon dioxide is present in the air.
Q3. What has caused air pollution?
Ans: Substances that cause air pollution are known as air pollutants. This pollutant is released into the air due to the burning of fossil fuel, from vehicles, or emitted from industries and agriculture.
Key Features
In this article, we have discussed air which is also regarded as the breath of life, the composition of air, etc.
The importance of air is maintaining the temperature of the earth, wind also blows due to the locomotion of air, and many other importances have been discussed in this article.
Air is composed of nitrogen, oxygen, carbon dioxide, argon, and helium.
Air pollution is defined as undesirable changes in the quality of air. It has many side effects, such as causing damage to buildings, monuments, plants, and animals.
Practice Questions
Q1. Which gas is regarded as the breath of life?
Q2. Is the breath of life energy?
Q3. Do we breathe the same air as our ancestors?
Q4. Why is the air we breathe so important?
Q5. Do we breathe to live?
FAQs on Breath Of Life Air and Its Role in Living Organisms
1. What is meant by Breath of Life Air in biology?
The term Breath of Life Air refers to oxygen (O₂), the essential gas in air required for cellular respiration in living organisms. Oxygen is called the “breath of life” because it enables cells to release energy from food.
- It makes up about 21% of Earth's atmosphere.
- It is required by most plants, animals, and microorganisms.
- It supports energy production in the form of ATP.
2. Why is oxygen called the breath of life?
Oxygen is called the breath of life because it is essential for aerobic respiration, the process that releases energy from food in cells. Without oxygen, most organisms cannot produce enough energy to survive.
- Oxygen helps break down glucose in mitochondria.
- This process produces ATP (adenosine triphosphate).
- Energy from ATP powers body functions such as movement, growth, and repair.
3. What is the composition of air that supports life?
Air that supports life mainly contains nitrogen (78%), oxygen (21%), and small amounts of other gases. Oxygen is the key life-supporting component.
- Nitrogen – 78%
- Oxygen – 21%
- Carbon dioxide – 0.04%
- Water vapor and noble gases – trace amounts
4. How does oxygen help in cellular respiration?
Oxygen helps in cellular respiration by acting as the final electron acceptor in the electron transport chain. This allows cells to produce large amounts of ATP.
- Glucose is broken down in glycolysis.
- Further reactions occur in the Krebs cycle.
- Oxygen accepts electrons to form water (H₂O).
- ATP is generated in the mitochondria.
5. How do humans obtain the breath of life from air?
Humans obtain the breath of life by inhaling oxygen into the lungs, where it diffuses into the blood. Oxygen is then transported to body cells.
- Air enters through the nose or mouth.
- Oxygen reaches the alveoli.
- It diffuses into capillaries and binds to hemoglobin.
- Blood carries oxygen to tissues.
6. What is the role of plants in maintaining the breath of life?
Plants maintain the breath of life by producing oxygen during photosynthesis. This process replenishes atmospheric oxygen used by living organisms.
- Plants absorb carbon dioxide.
- Using sunlight and chlorophyll, they produce glucose.
- Oxygen is released as a by-product.
7. What happens if there is not enough oxygen in the body?
If there is not enough oxygen in the body, a condition called hypoxia occurs, leading to reduced cellular energy production. Severe hypoxia can damage organs.
- Cells switch to anaerobic respiration.
- Lactic acid builds up.
- Symptoms include dizziness, fatigue, and shortness of breath.
8. What is the difference between breathing and respiration?
Breathing is the physical process of inhaling and exhaling air, while respiration is the chemical process of releasing energy from food inside cells. Both are essential for life but occur differently.
- Breathing occurs in the lungs.
- Cellular respiration occurs in mitochondria.
- Breathing supplies oxygen for respiration.
9. Can organisms survive without oxygen?
Some organisms can survive without oxygen by performing anaerobic respiration or fermentation. However, most complex organisms require oxygen.
- Yeast performs alcoholic fermentation.
- Certain bacteria are anaerobic.
- Humans rely mainly on aerobic respiration.
10. Why is air essential for the survival of living organisms?
Air is essential for survival because it supplies oxygen for respiration and carbon dioxide for photosynthesis. These processes maintain the balance of life on Earth.
- Animals use oxygen to produce energy.
- Plants use carbon dioxide to make food.
- This exchange maintains the oxygen–carbon dioxide cycle.
