I WONDER - What Does The Immune System Do? Me Pregunto - Qué Hace El Sistema Inmunológico?

The video tutorial explains the immune system's role in protecting the body from harmful substances known as antigens and pathogens, which include viruses, parasites, and bacteria. It describes how these pathogens can make us sick and details the two main functions of the immune system: preventing diseases from entering the body and attacking diseases that have already entered.

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