Why do we have blood and what does it do?

Why did the dinosaurs go extinct? Many of you have learned about the meteorite that scientists say hit the earth 66 million years ago and killed off many dinosaur species. But some dinosaurs survived, and the birds you see flying around today are their direct descendants! In this ...  Show more

Why are brothers and sisters so annoying? Why do siblings often look a lot alike? Why do siblings fight? Can your sister be your best friend? Why do we fight with our siblings even if we love them? But Why takes a look at the sibling relationship with Susan Dominus, author of The ...  Show more

Why does blood not stick to human skin like a permanent marker, yet stains things like clothes really badly? How does circulation work after an amputation? How many blood types are there? What does A B & O mean? If blood in your veins looks blue, why do we never see blue blood wh ...  Show more

If you’ve ever smacked a mosquito on your arm, you might have seen a little smear of red blood on your skin afterward. But just whose blood was it? Do we have the same blood as insects? We asked biologist Claire Rusch from the University of Washington to help us find the answer.G ...  Show more

Many people battling symptoms, conditions, or chronic illness are subjected to routine blood draws and tests. How can these routine blood draws affect the body? In this episode, I uncover important truths about blood draws and reveal why the blood testing and donation system is b ...  Show more

Knowing your blood group is handy information if you need a blood transfusion, or even an organ transplant. And it's essential information for the blood bank recruiting donors who match your blood type—and for people needing a blood product.