Transcription: All living organisms have to be able to sense and respond to change. Consider for example this turtle. He's sensing that his internal body temperature is getting too cold. He's responding to that change by climbing out of the water onto this log. He'll be able to sun himself on this log and that will increase his body temperature. Since he's a turtle, this takes some time but eventually he finds a nice warm spot on the log. After he's been sunning himself for a while, you're going to see him sense and respond to change again. This time something jumps in the water, scaring him. Did you see how ...
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