Final answer:
The normal respiratory rate for a child aged 1 to 8 years decreases with age from 30-60 to 18-30 breaths per minute and reaches 12-18 by adolescence, closely regulated by the brain's respiratory center.
Step-by-step explanation:
The normal respiratory rate of a child aged between 1 to 8 years gradually decreases as they grow. When they are under 1 year old, the normal respiratory rate ranges from 30 to 60 breaths per minute. However, as the child reaches around 10 years of age, the normal respiratory rate slows down to about 18 to 30 breaths per minute.
By the time they reach adolescence, their respiratory rate is similar to that of adults, which is 12 to 18 breaths per minute. Understanding the respiratory rate is crucial as it contributes to alveolar ventilation, which is the movement of air in and out of the alveoli, preventing the buildup of carbon dioxide. It is important to note that both the tidal volume and the respiratory rate are meticulously regulated by the respiratory center in the brain, especially when oxygen demand increases, such as during exercise or exertion.