How Long Can You Hold Your Breath?
INTRODUCTION
Carbon dioxide, produced from cellular respiration, is carried in the blood in three main forms:
brainstem and by the carotid bodies in the neck, which respond to changes in CO2 levels and pH levels. Unlike the brainstem, the carotid bodies also respond to plasma O2 levels. A raising of the arterial blood carbon dioxide levels above normal is called hypercapnia. Hypercapnia can result from insufficient ventilation to clear carbon dioxide from the lungs.This might occur with a lung disease that impairs carbon dioxide removal from the blood, even when ventilation is adequate. In general, increases in blood carbon dioxide levels lead to increases in ventilation. Conversely, hyperventilation (rapid shallow breathing) may drastically lower carbon dioxide levels in blood and will trigger a slowdown in ventilation. Oxygen levels also affect ventilation. Hypoxia results from insufficient fresh air reaching the lungs, the blood, and tissues. CAUTION: Students with respiratory ailments, such as asthma or allergies, should not participate in the breath-holding part of this activity |
Procedures
Record your answers in your journal
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