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
A low oxygen level in your blood is a good indicator of a COVID-19 infection, but what exactly does that mean and how do doctors test for it?
James Harrison's blood contains a rare and powerful antibody that's saved millions of Australian babies. Now, at age 81, after donating 1,173 times, he's hoping someone else will pick up where he left off.
The heart is crucial to life and the focus of love. Explore the parts of the heart and how your heart works, plus take a look at real pictures of human hearts with this gallery.
When you donate blood, your blood type is an important factor in how useful your donation may be. Just what are blood types?