Episode 4 Preview | Defend
Preview: Episode 4 | 30sVideo has Closed Captions
Uncover how the human body defends itself in an increasingly dangerous global environment.
Look at a nature survivalist, rancher twins, a doctor who survived Ebola and the recipient of a cutting-edge cancer therapy to uncover the wildly advanced biology that keeps us alive against all odds.
Problems playing video? | Closed Captioning Feedback
Problems playing video? | Closed Captioning Feedback
Episode 4 Preview | Defend
Preview: Episode 4 | 30sVideo has Closed Captions
Look at a nature survivalist, rancher twins, a doctor who survived Ebola and the recipient of a cutting-edge cancer therapy to uncover the wildly advanced biology that keeps us alive against all odds.
Problems playing video? | Closed Captioning Feedback
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Human: The World Within is available to stream on pbs.org and the PBS app.
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Clip: Ep4 | 2m 6s | An introduction into the amazing functions of the human body's immune system. (2m 6s)
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