Question

1
select the correct answer.
larry is taking a walk in the park. the pollen in the air makes him sneeze constantly. what line of defense is his immune system exhibiting?
a. first line of defense
b. second line of defense
c. third line of defense
d. fourth line of defense

Explanation:

The immune system's first line of defense includes physical and chemical barriers (like sneezing to expel foreign particles like pollen). Sneezing to remove pollen is part of the first line as it's a non - specific, external defense mechanism. The second line involves non - specific internal responses (e.g., inflammation), and the third is specific (adaptive) immunity. There is no fourth line of defense.

Answer:

A. first line of defense