Respiration Processes in Organisms Quiz

Study Notes

Respiration: The Process of Gaseous Exchange in Organisms

Respiration is a fundamental life process that involves the exchange of gases between an organism and its environment. It is the process by which an organism uses the food material to produce energy. The energy released during cellular respiration is immediately used to synthesize ATP, which is used to fuel all other activities in the organism.

Life Processes

Life processes are the biochemical and physiological processes that maintain the body's functions and are required for the survival of living beings. Some of the important life processes include nutrition, respiration, transportation, excretion, and metabolism.

Respiration in Organisms

Organisms have developed various methods to achieve respiration. For example, some organisms, like plants and aquatic animals, exchange gases through diffusion. In plants, the exchange of gases takes place through stomata by simple diffusion. In aquatic animals, such as fishes, water is taken in through their mouths and forced past the gills, where the dissolved oxygen is absorbed. In human beings, the passage of air can be written as nostril → trachea → bronchi → bronchioles → alveolar sac. The alveoli provide a surface where the exchange of gases can take place. Blood releases the dissolved CO2 into the alveoli and carries O2 from alveolar air. Hemoglobin in RBC of blood transports O2 from lungs to various tissues of the body.

Cellular Respiration

Cellular respiration involves the breakdown of food in the cell with the release of energy. Aerobic respiration is the type of respiration in which organisms use oxygen for burning food inside the cell, while anaerobic respiration is the respiration that occurs in the absence of oxygen and produces less energy. In anaerobic respiration in muscle cells, glucose is converted into pyruvate and, in the absence of oxygen, pyruvate is converted into lactic acid and energy. In anaerobic respiration in yeast, glucose is converted into pyruvate, and in the absence of oxygen, pyruvate is converted into ethanol, carbon dioxide, and energy.

Respiration in Humans

The human respiratory system has several parts, including the nasal chamber, pharynx, larynx, trachea, bronchi, lungs, and diaphragm. Air enters through the nostrils and passes through the trachea, bronchi, and bronchioles, ending in tiny air sacs called alveoli. The alveoli increase the surface area for the exchange of gases. During respiration, the diaphragm contracts and moves downward, causing the chest cavity to expand and air to enter the lungs. When exhaling, the diaphragm relaxes, and the chest cavity contracts, pushing air out of the lungs.

The Importance of Respiration

Respiration is crucial for the survival of living organisms. It provides the necessary oxygen for metabolism, which is used to produce energy, and it helps remove carbon dioxide, a waste product of metabolism. Without proper respiration, an organism would not be able to survive for very long.

Description

Test your knowledge on respiration, a vital process that involves the exchange of gases in organisms to produce energy. Explore topics like cellular respiration, the human respiratory system, and the importance of respiration for survival.