critical thinking micro

1. Individuals who smoke have much higher rates of lung infection. Explain which first-line defenses mechanisms may be impaired by smoking, allowing pathogens to more readily enter the lower respiratory tract.

2. The diagnosis of tuberculosis involves the observation of lung structures called tubercles on an X ray. What immunologic process leads to the formation of tubercles, and what type of immune cells may comprise these lesions?

3. Provide an explanation in support of or refuting the following statement: "Humans would never develop natural immunity to a novel biological agent created in a laboratory."

4. Explain how super-antigens, such as toxic shock syndrome toxin produced by  Staphylococcus aureus, often lead to the development of life-threatening symptoms in an infected individual.