What color is blood REALLY? (Full length version)

Science Mom investigates what color blood REALLY is, and why. Join her to learn why veins are blue, how confirmation bias shapes our thinking--and see cute cartoons of hemoglobin too.

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The items put into the soda during the clip at the very end were mentos, sand, and baking soda, in that order. I did 5 lessons with mentos on the day that clip was filmed, and in each repetition the sand went significantly higher than mentos. And baking soda topped them both. But that's a topic for another video. :)

A big thank you to the many friends and colleagues who allowed me to interview and record them for this video. I took artistic liberty with the rendering of the cartoon faces. Any resemblance between the cartoon face and the person's actual appearance is entirely coincidental. Just FYI.

The article referenced in the video is, "Why do veins appear blue? A new look at an old question." by Kienle et al, Applied Optics, Vol 35, issue 7, p 1151-1160. Published in 1996.

The music in the video is from the iMovie library (Half Moon Bay Long.)