That veins contain blue blood. I learned it from the textbook and believed it for a year, until I heard my parents insist it was red. I thought there is no way that could be true, the textbook clearly said otherwise! So I went back to check the book thoroughly and wouldn’t you know it - on page 32 there was a tiny footnote on the bottom saying that all blood is red but the pictures will show it as blue for clarity - followed by a hundred pages of glorious full-color illustrations of red-and-blue circulatory systems. Thanks a lot, textbook!
That veins contain blue blood. I learned it from the textbook and believed it for a year, until I heard my parents insist it was red. I thought there is no way that could be true, the textbook clearly said otherwise! So I went back to check the book thoroughly and wouldn’t you know it - on page 32 there was a tiny footnote on the bottom saying that all blood is red but the pictures will show it as blue for clarity - followed by a hundred pages of glorious full-color illustrations of red-and-blue circulatory systems. Thanks a lot, textbook!