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the green pigment in plants that can absorb the sun's energy


a substance made by combining two or more elements


an energy releasing process that does NOT require oxygen


the type of proteins that speed up chemical reactions, such as in digestion


the most common compound in living things

amino acids

the smaller molecules that are the building blocks of proteins


the type of organic compound that meat, beans, nuts contain alot of


element found in all organic compounds

selectively permeable

a membrane that allows some substances to pass through but not others


a chemical substance that cannot be broken down into simpler substances

nucleic acids

DNA and RNA are examples of this type of organic compound in organisms


sugars and starches are examples


the type of organic compound that stores the most energy

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