The lecture on innate immunity provides undergraduate students with a fundamental understanding of the body’s initial defense mechanisms against pathogens. It covers topics such as physical barriers like skin and mucous membranes, as well as cellular and molecular components like phagocytes, natural killer cells, and antimicrobial proteins. Additionally, the lecture explores the inflammatory response and the role of pattern recognition receptors in identifying pathogens. Through this lecture, students gain insights into the innate immune system’s critical role in protecting the body from infections and maintaining overall health.