Organisms at the base of the food chain that photosynthesize – for example, plants and algae – use the carbon in Earth’s atmosphere.
They have the same ratio of carbon-14 to carbon-12 as the atmosphere, and this same ratio is then carried up the food chain all the way to apex predators, like sharks.
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Challenge students to explore the natural and physical world with this collection of science worksheets and activities.
From cells, to organisms, to ecology, use these life science worksheets and quizzes to supplement and support your life science teaching.
Uber has already revolutionized transportation by making it simple.
Now Uber plans to make it even more accurate and trouble-free, using current, high-resolution satellite imagery from Digital Globe to identify the best pick-up and drop-off locations.
is a technique used by scientists to learn the ages of biological specimens – for example, wooden archaeological artifacts or ancient human remains – from the distant past.
It can be used on objects as old as about 62,000 years.