The following Topics and Sub-Topics are covered in this chapter and are available on MSVgo:
Respiration in organisms is a chapter taught in class 7 that delves into the biology subject of science. Respiration in animals takes place through specialised cells called alveoli that form the respiratory system unit. You must have heard about the mitochondria that are a part of the cell. It is the powerhouse of the cell. To produce energy, it requires nutrients along with oxygen. Oxygen is vital for the body organs to perform any function. Energy is derived from food along with oxygen. The respiratory system helps a body to sustain and convert food into energy.
Breathing enables an organism to inhale oxygen and exhale carbon dioxide. Oxygen is required to convert the food that we eat into energy. The ATPs that are released after the conversion takes place in the presence of oxygen.
Cellular respiration is the interchange of cellular oxygen and carbon dioxide with the surroundings. The air that we breathe goes to finer parts of our body, such as cells. The mitochondrion is the site inside the cell where cellular respiration takes place. Oxygen is also responsible for releasing carbon dioxide from the cell when the oxygen interacts with the food.
Glucose and oxygen meet inside the mitochondria to release carbon dioxide and water to the surroundings. This carbon dioxide is carried away with the blood to the lungs.
We breathe out carbon dioxide released when the oxygen reacts with the carbohydrates present in the cell.
Breathing in and out is a continuous process that keeps happening all the time till we die. The heart needs the energy to keep pumping the blood across the body, and hence we need oxygen to convert the food to energy. Respiration starts when we take air from the nostrils from the surroundings. It moves to the lungs, where we have alveoli that exchange the gases from the blood. The chest that holds the lungs lay on a muscle sheet called the diaphragm. The ribs and diaphragm movement causes the breathing in and out phenomenon. When we breathe in air, the diaphragm moves down, which makes the ribs move outwards. While we are releasing air, the diaphragm moves back up and the ribs contract.
There are two kinds of respiration, namely aerobic respiration and anaerobic respiration. Let’s look at both in detail.
Aerobic Respiration: It takes place in the presence of oxygen and leads to the release of a high energy amount. Human beings are the best examples of aerobic respiration because we breathe in oxygen. The cells release carbon dioxide and water.
Anaerobic Respiration: It is a type of respiration that commonly happens in yeast and does not require oxygen. The respiration occurs in the absence of oxygen and results in the release of very low energy. Human beings also undergo anaerobic respiration in certain conditions. The released product in the muscle cells that undergo anaerobic respiration is lactic acid, and yeast releases ethanol.
Other animals have a slightly different respiratory system when compared to humans. Although the primary function is similar to the human respiratory system, it exhales the surroundings’ gases. Let’s check that in some more details.
Breathing in cockroaches: They have a small opening called spiracles on their sides of the body. The trachea is the air tube that runs inside their body and opens up at the spiracles for exchanging gases. The trachea is connected to the various body cells where internal cellular respiration takes place.
Breathing in earthworms: Earthworms breathe through their slimy and moist skin. The air can pass through their skin. Similarly, frogs also can breathe through their skin, although they have lungs too.
Yes, plants also breathe through stomata that are pore openings on the backside of the leaves. The plants can also absorb oxygen from their roots. The central feature of plants is that all their parts can independently respire. You must have read that plants take carbon dioxide and release oxygen during the day.
Respiration in organisms is an essential phenomenon that deals with exchanging gases from the surroundings and the body. We have a dedicated respiratory system with a fundamental unit called alveoli that carries out the gas exchange process inside the body. It is situated in our lungs, where the blood takes the oxygen to the body’s different parts. Different organisms have different types of respiratory systems.
You can check the MSVgo video learning app to know more about the respiratory system of other organisms.