That's what wood pretty much is. It gets put into plants, and then it gets put into the things that eat the plants.
So that could be us. Now why is this even interesting? I've just explained a mechanism where some of our body, even though carbon is the most common isotope, some of our body, while we're living, gets made up of this carbon thing. Well, the interesting thing is the only time you can take in this carbon is while you're alive, while you're eating new things. Because as soon as you die and you get buried under the ground, there's no way for the carbon to become part of your tissue anymore because you're not eating anything with new carbon And what's interesting here is once you die, you're not going to get any new carbon And that carbon that you did have at you're death is going to decay via beta decay-- and we learned about this-- back into nitrogen So kind of this process reverses.
So it'll decay back into nitrogen, and in beta decay you emit an electron and an electron anti-neutrino. I won't go into the details of that. But essentially what you have happening here is you have one of the neutrons is turning into a proton and emitting this stuff in the process.
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Now why is this interesting? So I just said while you're living you have kind of straight-up carbon And carbon is constantly doing this decay thing. But what's interesting is as soon as you die and you're not ingesting anymore plants, or breathing from the atmosphere if you are a plant, or fixing from the atmosphere. And this even applies to plants. Once a plant dies, it's no longer taking in carbon dioxide from the atmosphere and turning it into new tissue. The carbon in that tissue gets frozen. And this carbon does this decay at a specific rate. And then you can use that rate to actually determine how long ago that thing must've died.
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So the rate at which this happens, so the rate of carbon decay, is essentially half disappears, half gone, in roughly 5, years. And this is actually called a half life. And we talk about in other videos.
This is called a half life. And I want to be clear here. You don't know which half of it's gone. It's a probabilistic thing. You can't just say all the carbon's on the left are going to decay and all the carbon's on the right aren't going to decay in that 5, years. So over the course of 5, years, roughly half of them will have decayed. Now why is that interesting?
Section 2: Relative-Age Dating of Rocks
Well, if you know that all living things have a certain proportion of carbon in their tissue, as kind of part of what makes them up, and then if you were to find some bone-- let's just say find some bone right here that you dig it up on some type of archaeology dig. And you say, hey, that bone has one half the carbon of all the living things that you see right now.
It would be a pretty reasonable estimate to say, well, that thing must be 5, years old. Even better, maybe you dig a little deeper, and you find another bone. Maybe a couple of feet even deeper. In January , Quora launched a blogging platform allowing users to post non-answer content on their profiles. Quora launched a full-text search of questions and answers on its website on March 20, ,  and extended the feature to mobile devices in late May Quora acquired the online community website Parlio in March In October , Quora launched a Spanish version of its website to the public.
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Retrieved 1 October Retrieved February 12, Retrieved April 6, Retrieved March 29, Assuming no potassium has been lost to any process other than radioactive decay, what is the approximate absolute age of the rock? Carbon and carbon are both found in living organisms. What is the difference between carbon and carbon?
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The boundaries between various periods on the geologic time scale are based primarily on:. What property of index fossils makes them so useful for subdividing geologic time? What features of rock strata would be most useful for a geologist to analyze in order to correlate rock layers in two different locations? How does the principle of faunal succession allow geologists to correlate rock strata in different geographic locations? An igneous rock intrudes into three tilted layers of sedimentary rock. Which set of relative dating methods is most useful to determine the chronological order of formation of the rocks?