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Biology Vocabulary


compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the human body


a single sugar molecule


macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes

fatty acid

an organic acid that is contained in lipids, such as fats or oils

amino acid

basic building blocks of protein molecules

nucleic acid

an organic compound, either RNA or DNA, whose molecules are made up of one or two chains of nucleotides and carry genetic information


building block of a nucleic acid (DNA and RNA)


a simple molecule that can combine with other like or unlike molecules to make a polymer


a naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers


specialized proteins that speed up chemical reactions


the substance acted upon by an enzyme or ferment

activation energy

the minimum amount of energy required to start a chemical reaction


substance that speeds up the rate of a chemical reaction


a substance or molecule that participates in a chemical reaction


a chemical substance formed as a result of a chemical reaction


macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes

ORHS 9th Biology


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