Uploaded July 2025 | Updated September 2026, 2 weeks ago

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Across life on Earth, blood comes in red, blue, green, purple, even clear. But why? And what makes your blood different from mine? This video will teach you everything you need to know about the strange world of blood—what it does, why it varies, and why we can’t live without it.

References: sites.google.com/view/be-smart-blood-types

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