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What is carbon? Atoms – Chemistry

By |2019-02-28T05:45:37-07:00June 1st, 2017|Biology, Chemistry|

Diagram of a carbon atom Where does carbon come from? When a star has changed all of the hydrogen atoms into helium, it begins to convert the helium atoms into carbon atoms and oxygen atoms. All of the carbon in the universe was made inside stars. More about stars What is hydrogen? Science [...]

Yeast cells – Cell biology

By |2018-04-16T10:32:23-07:00May 29th, 2017|Biology|

A yeast cell Yeast cells are a very common kind of eukaryote cell. They vary in size, but are usually about four thousandths of a millimeter (4 microns) in diameter, too small to see without a microscope. Yeast are one-celled creatures that eat starches and sugars. Enzymes inside the mitochondria in the yeast cells [...]

What is photosynthesis? Plant Biology

By |2018-04-16T00:37:36-07:00May 29th, 2017|Biology|

Chloroplasts (seen through a microscope) Photosynthesis is the way some cells on Earth pull in light from the sun and use it to make energy to repair and reproduce themselves. The first cells could not photosynthesize (foe-toe-SIN-the-size). They got food by breaking apart hydrocarbon molecules. But a little more than three billion years ago, [...]

Yeast Project – Bread-making – Cell biology

By |2017-05-28T22:06:37-07:00May 28th, 2017|Biology|

A boy making bread You can see what yeast does by making bread at home. It doesn't matter what recipe you use as long as the recipe calls for yeast, but here's a good recipe for bread. You can buy little paper packets of yeast at any big grocery store, and all you [...]