Which of the following is the correct order of the three lines of defense?
A) barriers that exclude pathogensadaptive immunityinnate immunity
B) barriers that exclude pathogensinnate immunityadaptive immunity
C) innate immunityadaptive immunitybarriers that exclude pathogens
D) apaptive immunitybarriers that exclude pathogensinnate immunity
E) apative immunityinnate immunitybarriers that exclude pathogens

Question

Which of the following is the correct order of the three lines of defense?
A) barriers that exclude pathogens>>adaptive immunity>>innate immunity
B) barriers that exclude pathogens>>innate immunity>>adaptive immunity
C) innate immunity>>adaptive immunity>>barriers that exclude pathogens
D) apaptive immunity>>barriers that exclude pathogens>>innate immunity
E) apative immunity>>innate immunity>>barriers that exclude pathogens

Quizplus · Accepted Answer

The first line of defense includes physical and chemical barriers that exclude pathogens from entering the body, such as the skin, mucous membranes, and stomach acid. The second line of defense is the innate immune system, which includes phagocytic cells, natural killer cells, complement proteins, and inflammation. The third line of defense is the adaptive immune system, which includes B and T lymphocytes that mount a specific response to pathogens. Therefore, the correct order is barriers that exclude pathogens>>innate immunity>>adaptive immunity, which is represented by option B.

Which of the Following Is the Correct Order of the Three