| A | B |
|---|
| organic molecule | carbon-based molecule |
| inorganic molecule | non-carbon-based molecule |
| hydrocarbon | organic molecule composed of only carbon and hydrogen atoms |
| functional group | group of atoms within a molecule that interacts in predictable ways with other molecules |
| hydrophilic | attracts water molecules |
| monomer | small molecular unit that is the building block of a larger molecule |
| polymer | long chain of small molecular units |
| carbohydrate | organic compound made of sugar molecules |
| monosaccharide | sugar containing one sugar unit |
| disaccharide | sugar containing two monosaccharides |
| polysaccharide | long polymer chain made up of simple sugar monomers |
| starch | polysaccharide in plant cells that consists entirely of glucose monomers |
| glycogen | polysaccharide in animal cells that consists of many glucose monomers |
| cellulose | polysaccharide consisting of glucose monomers that reinforces plant-cell walls |
| lipid | one of a class of water-avoiding compounds |
| hydrophobic | avoids water molecules |
| fat | organic compound consisting of a three-carbon back-bone (glycerol) attached to three fatty acids |
| saturated fat | fat in which all three fatty acids chains contain the maximum possible number of hydrogen atoms |
| unsaturated fat | fat with less that the maximum number of hydrogens in one or more of its fatty acids |
| steroid | lipid molecule with four fused carbon rings |
| cholesterol | steroid molecule present in the plasma membranes of animal cells |
| protein | polymer constructed from a set of 20 amino acid monomers |
| amino acid | monomer that makes up proteins; contains carboxyl and amino functional groups |
| polypeptide | chain of linked amino acids |
| denaturation | loss of normal shape of a protein due to heat or other factor |
| activation energy | minimum amount of energy required to trigger a chemical reaction |
| catalyst | agent that speeds up chemical reactions |
| enzyme | specialized protein that catalyzes the chemical reactions of a cell |
| substrate | specific reactant acted on by an enzyme |
| active site | region of an enzyme into which a particular substrate fits |
