Chapter 1: What is Biology

Trachea is made from cartilage. Leads to bronchi (Fig. 16.6, 16.7). Bronchi are branched tubes of cartilage. Leads to lung. Bronchioles are smaller branches of bronchi. Alveoli is where gas exchange with circulatory system occurs. Lobular sacs embedded in capillaries. (Fig. 16.9) Oxygen and carbon dioxide exchanged here (Fig. 16.10) Lung (Fig ... ................
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