Critical Thinking

49.

Name each of the structures of the respiratory tract shown, and state whether each has a relatively large or small normal microbiota.

Diagram of respiratory system. D is the space in the nose this leads to E (a tube behind the mouth). This leads to G (a cartilage ringed tube that leads to the lungs). F is a larger region just above G. G branches into 2 tubes labeled A, these branch and branch again to become B. The very end of B is C.

Figure 22.30 (credit: modification of work by National Cancer Institute)

50.

Cystic fibrosis causes, among other things, excess mucus to be formed in the lungs. The mucus is very dry and caked, unlike the moist, more-fluid mucus of normal lungs. What effect do you think that has on the lung’s defenses?

51.

Why do you think smokers are more likely to suffer from respiratory tract infections?

52.

Why might β-lactam antibiotics be ineffective against Mycoplasma pneumoniae infections?

53.

Why is proper antibiotic therapy especially important for patients with tuberculosis?

54.

What role does the common cold have in the rise of antibiotic-resistant strains of bacteria in the United States?

55.

Why is it highly unlikely that influenza A virus will ever be eradicated, like the smallpox virus?

56.

Why are fungal pulmonary infections rarely transmissible from person to person?