Circulatory System
The heart is a hollow, muscular organ that maintains blood circulation throughout the body. Learn how the circulatory system - your heart, blood vessels and blood - bring nutrients to the body.
How White Matter Helps the Brain's Gray Matter Function
Bruce Willis Has Aphasia. What Is It and What Causes It?
Can Our Bodies 'Learn' to Withstand Frigid Temperatures?
What Is Saliva and How Does It Change the Taste of Food?
The World's Longest Poop Story Is a Crock of, Well ...
When You Have to Go But Don't Want People to Know
Does Oxytocin Make Us Fall in Love?
5 Ways Homeostasis Keeps Your Body Humming Along
Is It Possible to Get Taller as an Adult?
Do You Have One of the 6 Rarest Eye Colors in the World?
Why Do Babies' Eyes Change Color?
There Are 6 Different Eye Shapes. Which One Is Yours?
'Man Flu' Could Be a Real Thing
Sugars in Human Breast Milk Act as Antibacterial Agents
Does mouthwash affect your immune system?
Kidney Stones Are Excruciating, But the Source of Pain Is Surprising
Why Do We Do a Little Dance When We Have to Pee?
Do You Turn the Door Key and Have to Pee? It May Be All in Your Brain
The Lymph System
What is lymph?
How One Key Protein May Help Tendons Enhance Athletic Performance
What Are Muscle 'Knots' and How Do You Get Rid of Them?
Children Can Regrow Their Fingertips. How Cool Is That?
What Happens When the Wind Is Knocked Out of You?
The Science Behind Why We All Have Snot
Why Breathing Through Your Nose Is Best
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The heart is one of the strongest muscles in the body. Learn about this extremely vital part of the body.
When you donate blood, your blood type is an important factor in how useful your donation may be. Just what are blood types?
When you cut yourself accidentally, do you ever wonder what makes up this thing we call blood? It's pretty amazing stuff, considering how it wards off infections while supplying nutrients to every cell in the human body.
The heart is a vital organ that basically serves as a pump. Learn about heart chambers and valves, blood flow, the heart's electrical system and blood supply. Read more about how this amazing organ works.