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Which of the following is not the part of first line of defense?

Correct answer: C. Interferon

  • A. Sebum
  • B. Perspiration
  • C. Interferon
  • D. Epidermis

Explanation

The first line of defense is formed by external barriers, such as skin and mucous membranes. The second line of defense is provided by phagocytes, natural killer cells, antimicrobial proteins, and inflammatory response. Important antimicrobial proteins include lysozyme, complement proteins, and interferons. Interferons are small proteins, secreted by virally infected cell lymphocytes. They create anti-viral resistance in healthy uninfected body cells. The adaptive immune system forms the third line of defense of the body. It depends on two types of lymphocytes called B-cells and T-cells.

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