| A | B |
|---|
| atoms | smallest unit of matter that cannot be broken down by chemical means |
| electrons | elementary particle that carries a negitive charge |
| element | a substance composed by a single type of atom |
| ion | electricly charged atom or molecule |
| compound | substance that is made up of more than one kind of atom |
| covalent bond | formed when two atoms share electrons (very strong bonds) |
| molecule | a group of atoms held together by covalent bonds |
| ionic bond | a bond caused by the attraction between positive and negative ions |
| hydrogen bonds | a very weak chemical bond that forms between two polar molecules |
| polar molecules | molecules that have unequal areas of charge |
| acid | any compound that forms hydrogen ions when dissolved in water |
| pH scale | a scale that relates the amount of hydrogen ions from one solution to another |
| base | any substance that ionizes to form hydroxide ions when dissolved in water |
| carbohydrate | organic compound formed of carbon, hydrogen, and oxygen in a 1:2:1 ratio |
| polysaccharide | carbohydrate made by linking individual sugars together to form long chains |
| starch | a common storage form of gluscose composed of long chains made of hundreds of glucose molecules |
| glycogen | long chains of glucose-containing fragments |
| cellulose | carbohydrate that is the main structural component of cell walls in plants |
| lipid | organic molecule that do not dissolve in water |
| saturated fat | a fat that has no C=C bonds ( has maximum number of hydrogen atoms) |
| unsaturated fat | a fat that has C=C bond |
| steroid | a class of lipids that contain cholesterol and hormones |
| protein | organic compound formed of one or more chains of polpeptides |
| collagen | fibrous structural protein that forms skin, ligaments, tendons, and bones |
| enzyme | protein that catalyzes a chemical reaction |
| catalyst | a material that speeds up a chemical reaction without being distroyed |
| amino acid | subunits of proteins |
| polypeptide | long chain of amino acids (form proteins) |
| nucleic acid | long chains of small repeating nucleotides (form DNA & RNA) |
| nucleotide | subunit of nucleic acids made of a nitrogenous base, a sugar, and a phospate group |
| DNA | the nuceic acid that forms hereditary information |
| what DNA stands for | deoxyribonucleic acid |
| RNA | a nucleic acid that makes proteins |
| what RNA stands for | ribonucleic acid |
| ATP | energy currency of the cell made of an organic base, a sugar, and three phosphate groups |
| what ATP stands for | adenosine triphosphate |
| triphosphate | a molecule that has three phosphate groups |
