Hingamistsükkel

Hingamistsükkel, also known as the respiratory cycle, refers to the complete sequence of events involved in breathing. It encompasses both the process of taking air into the lungs, known as inhalation or inspiration, and expelling air from the lungs, known as exhalation or expiration. This cycle is fundamental to gas exchange, allowing the body to obtain oxygen necessary for cellular respiration and to eliminate carbon dioxide, a waste product of metabolism.

The mechanics of the hingamistsükkel involve the coordinated action of respiratory muscles, primarily the diaphragm and the intercostal muscles. During inhalation, the diaphragm contracts and flattens, while the external intercostal muscles contract, lifting the rib cage upwards and outwards. These actions increase the volume of the thoracic cavity, leading to a decrease in intra-pulmonary pressure below atmospheric pressure. Consequently, air flows into the lungs.

Exhalation is typically a passive process at rest. The diaphragm and external intercostal muscles relax, causing the thoracic cavity to decrease in volume. This increases intra-pulmonary pressure above atmospheric pressure, forcing air out of the lungs. During forced exhalation, such as during exercise or coughing, the internal intercostal muscles and abdominal muscles contract to further reduce the thoracic volume. The rhythmic nature of the hingamistsükkel is controlled by the respiratory centers in the brainstem, which regulate the rate and depth of breathing in response to the body's metabolic needs.