Components of innate immunity are –
**Core Concept**
The innate immune system is the first line of defense against infections, comprising physical barriers, cellular responses, and molecular mechanisms that provide immediate protection against pathogens. It is non-specific, meaning it does not recognize specific pathogens, but rather responds to general patterns of microbial presence.
**Why the Correct Answer is Right**
Innate immunity involves the activation of immune cells such as neutrophils and macrophages, which release granules containing antimicrobial peptides and enzymes to eliminate pathogens. The complement system, a group of proteins that work together to eliminate pathogens, is also a component of innate immunity. Additionally, the innate immune system includes the production of cytokines, which are signaling molecules that recruit immune cells to the site of infection.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a correct component of innate immunity. While the term "adaptive immunity" is related to the topic, it refers to the specific immune response that occurs after exposure to a pathogen, rather than the immediate non-specific response of innate immunity.
**Option B:** This option is not a correct component of innate immunity. While the term "inflammation" is related to the topic, it is a result of the immune response, rather than a component of the innate immune system itself.
**Option C:** This option is not a correct component of innate immunity. While the term "hypersensitivity reactions" is related to the topic, it refers to a specific type of immune response that occurs after exposure to a pathogen, rather than a component of the innate immune system.
**Clinical Pearl / High-Yield Fact**
The innate immune system provides immediate protection against infections, but it is not specific to individual pathogens. This is why it is often referred to as the "first line of defense" against infections.
**Correct Answer:** C. Neutrophils, macrophages, complement system, and cytokines are all components of the innate immune system.