Chapter 45, Problem 1TYU

Innate immune responses include all but (a) inflammation (b) antigen-antibody complexes (c) binding of PAMPs with pattern recognition receptors (d) complement (e) phagocytosis

Summary Introduction

Introduction: A complex network of cells, tissues, and organs that work collectively for the protection of the body and fight against the pathogens or foreign substances is known as the immune system. The immune system is made up of several components such as immune cells, tissues, organs, and chemical mediators that destroy and eliminate foreign substances from the body.

Answer to Problem 1TYU

Correct answer: Innate immune responses do not include antigen-antibody complexes.

Hence, the correct answer is option (b).

Explanation of Solution

Reason for the correct answer:

The antigen-antibody complex is formed when antibodies (Y-shaped structure) combine with two molecules of antigens on its surface. These complexes directly promote or destroy the pathogens. The process of formation of the antigen-antibody complex is a part of adaptive immunity, not innate immunity (inborn). Adaptive immunity or acquired immunity is the type of immunity that is gained by the body over the lifetime by encountering and learning how to target and destroy specific pathogens that invade the body.

Option (b) is given as “antigen-antibody complexes”.

The process of formation of the antigen-antibody complex is a part of adaptive immunity, not innate immunity.

Hence, the correct answer is option (b).

Reasons for the incorrect answers:

Option (a) is given as “inflammation”.

Inflammation is an early defense process by which the body responds to an injury or infection. The innate immune response includes inflammation.

Hence, option (a) is incorrect.

Option (c) is given as “binding of PAMPs with pattern recognition receptors”.

The antigens, such as pathogen-associated molecular patterns (PAMP) trigger the innate immunity.

Hence, option (c) is incorrect.

Option (d) is given as “complement”.

Complements are the cluster of inactivated signaling proteins that stimulate (when get activated) the release of other chemical mediators to promote inflammation, chemotaxis, and phagocytosis. The innate immune response includes complement proteins.

 Hence, option (d) is incorrect.

Option (e) is given as “phagocytosis”.

Phagocytosis is a process in which phagocytes are involved in engulfing, destroying, and removing pathogenic microorganisms and foreign debris from the body. The innate immune response includes phagocytosis.

Hence, option (e) is incorrect.

Hence, the options (a), (c), (d), and (e) are incorrect.

Conclusion

Innate immune responses do not include antigen-antibody complexes. Antigen-antibody complexes belong to acquired immunity. Acquired immunity is acquired over a lifetime. It is antigen-dependent and antigen-specific.