hengitystoiminta

Hengitystoiminta refers to the physiological processes involved in breathing, the exchange of gases between an organism and its environment. This vital function ensures the supply of oxygen necessary for cellular respiration and the removal of carbon dioxide, a metabolic waste product. The process can be broadly divided into ventilation and gas exchange.

Ventilation, or breathing, is the mechanical movement of air into and out of the lungs. In mammals, this is achieved through the coordinated action of the diaphragm and intercostal muscles. Inhalation, an active process, increases the volume of the thoracic cavity, drawing air into the lungs. Exhalation, typically a passive process, decreases the volume, forcing air out.

Gas exchange occurs in the alveoli, tiny air sacs in the lungs. Here, oxygen from inhaled air diffuses across a thin membrane into the bloodstream, while carbon dioxide from the blood diffuses into the alveoli to be exhaled. This diffusion is driven by differences in partial pressures of the gases.

In humans, the respiratory system, comprising the nose, pharynx, larynx, trachea, bronchi, and lungs, facilitates this process. The nervous system, particularly the brainstem, regulates the rate and depth of breathing, responding to changes in blood oxygen and carbon dioxide levels. Various factors, including physical activity, altitude, and medical conditions, can affect hengitystoiminta.