Why is your blood red? How do scabs form? What’s the difference between different blood types? It’s Alive! Yes, your blood is alive. Find out what it does to keep YOU alive. Blood Vessels What’s the difference between arteries, veins, and capillaries? Red Blood Cells Why are red blood cells red and why does it matter? White Blood Cells Look out, invading germs! White blood cells have several tactics to make you retreat. All About Scabs The (somewhat) gross but (truly) fascinating world of scabs. Blood Types: What's the Difference? A+, O-, AB+ … what does it all mean anyway?