Respiratory Cycle - definition and human lungs
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Respiratory Cycle is one repetition of the pattern of inhalation (BREATHING air into the LUNGS), OXYGEN-CARBON DIOXIDE EXCHANGE, and exhalation (breathing air out of the lungs). In health a typical adult completes 15 to 20 respiratory cycles a minute, called the RESPIRATION RATE. The brainstem regulates the respiratory cycle in response to feedback mechanisms from other body systems that indicate oxygen needs and consumption.
See also AEROBIC FITNESS; BREATHING EXERCISES; DYSPNEA; HYPERVENTILATION; TACHYPNEA.