| How many amino acids are used in proteins? | 20 |
| what elements does an amino acid contain? | Carbon, hydrogen, oxygen, nitrogen and some sulfur. |
| what are amino acids attached by? | peptide bonds |
| primary structure | the order in which amino acids are arranged in a protein |
| secondary structure | chains of amino acids coil up and fold into pleats that are held together by hydrogen bonds. Coil and pleats are the secondary structure. |
| tertiary structure | coiled chains of amino acids fold into a ball thats held together by weak bonds (hydrogen) and strong bonds (disulfide bonds) |
| globular protein | protein that has a roughly spherical shape. |
| what elements do carbohydrates contain? | carbon, hydrogen and oxygen |
| monosaccharides | single units from which all the other carbohydrates are built (eg glucose and fructose) |
| alpha glucose | H
OH |
| beta glucose | OH
H |
| disaccharides | when two monosaccharides are joined together in a condensation reaction (eg. maltose and sucrose) |
| polysaccharides | polymers made up of monosaccharides |
| starch | molecules made up of two polysaccharides: amylose and amylopectin (polymers of glucose) |
| cellulose | polysaccharide made up of glucose molecules. Cellulose molecules are long and straight. Several cellulose molecules can lie side by side to from microfibrils. Microfibrils strengthen the plant cell wall. |
| glucose + glucose = | maltose |
| glucose + fructose = | sucrose |
| triglyceride | make up plant oils and animal fats. consists of a molecule of glycerol with 3 fatty acids attached to it. |
| saturated fatty acid | where every carbon atom is joined via a single bond |
| unsaturated fatty acid | where one or more of the bonds is a double bond |
| polyunsaturated | fatty acid with many double bonds |
| phospholipid | a molecule of glycerol, 2 fatty acids and 1 phosphate group. cell membranes are made from a double layer of phospholipids. |
| metabolism | sum of biochemical reactions taking place in a cell. |
| metabolic pathway | a single chain of biochemical reactions in a cell. |
| enzymes | acts as a catalyst to speed up metabolic reactions. globular proteins involved in breaking down and building up molecules. |
| effect of high temperature on enzymes | atoms of the enzyme molecule vibrate more rapidly and break the weak bonds that hold the tertiary structure together. enzyme denatured. |
