The Human Body
~37 trillion cells of you, organized into a handful of systems that have to keep each other alive every second of every day.
The human body is the most thoroughly studied biological system in history and still one of the least fully understood. It is a coordinated collection of ~37 trillion cells, organized into a handful of organ systems that have to keep each other alive every second of every day. When it works, you don't notice it. When it doesn't, you notice nothing else.
Articles in this cluster
How the Human Body Works
A tour through the cardiovascular, respiratory, digestive, nervous, endocrine, immune, muscular, skeletal, urinary, and reproductive systems.
The Science of Aging
The cellular and molecular reasons your body changes over time — and the research aimed at slowing the process down.
The Brain and How Memory Works
How experience becomes a memory, why retrieval is reconstructive, and the four kinds of memory you've got.
The Gut Microbiome
The 38 trillion microbes that train your immune system and digest food you can't break down yourself.
Top 10 Fascinating Facts About Human DNA
The molecule that defines you, in ten surprising facts.
Understanding Viruses
What your immune system is actually fighting, and why some pathogens are nearly impossible to clear.
How to read this cluster
Start with How the Human Body Works for the structural overview. To dig into the parts that change as you get older: The Science of Aging explains the cellular story. For curious learners of the genetic underpinnings: Top 10 Facts About Human DNA is the right starting point.
Related sub-pillars
Return to the main Biology resources hub · Browse: human biology · anatomy · organ systems · aging
