
Body & Immune System
Why Do Mosquito Bites Itch?
The itch is not from the bite itself. It comes from your own immune system reacting to mosquito saliva. Here is what is actually happening under your skin.
mosquitoitch

Health
How Do Vaccines Work?
Vaccines train your immune system before the real germ arrives. Here's exactly what happens inside your body — explained simply.
healthvaccines

Biology
How Do Viruses Work?
Viruses cannot eat, move, or reproduce on their own. They are barely alive. Yet they have shaped human history more than almost any other force on Earth. Here is how they do it.
virusesbiology

Human Body
Can the Human Body Heal Itself From Anything?
The human body is one of the most sophisticated self-repair systems in nature, but its healing powers have real limits.
human bodyhealing