| A | B |
|---|
| carbohydrate | a molecule composed of sugar subunits - contains carbon, hydrogen, oxygen in a 1:2:1 ratio |
| polymer | a molecule composed of 3+ subunites |
| monosaccharide | a single sugar unit (ex. glucose, galactose, fructose) |
| disaccharide | a sugar formed by joining 2 monosaccharide units (ex. sucrose, maltose, lactose) |
| dehydration synthesis | larger molecules are formed by removing water from two smaller molecules |
| hydrolysis | larger molecules are split into smaller molecules by adding water |
| polysaccharide | carbohydrate composed of many single sugar subunits |
| starch | a carbohydrate used to store energy in plants |
| glycogen | a carbohydrate used to store energy in animals |
| cellulose | a plant polysaccharide that makes up cell walls (we can't digest it) |
| triglyceride | a lipid composed of glycerol and three fatty acids |
| fat | a lipid composed of glycerol and saturated fatty acids; solid at room temperature |
| oil | a lipid composed of glycerol and unsaturated fatty acids; liquid at room temperature |
| phospholipid | a lipid with a phosphate molecule attached to glycerol molecule - makes the molecule polar - major part of cell membranes |
| wax | a long-chain lipid that is insoluble in water (waterproof coating on plants, animal feathers, fur) |
| protein | a chain of amino acids that form the structural part of cells or act as antibodies or enzymes |
| amino acid | a chemical that contains nitrogen (amino group); linked together to form proteins |
| peptide bond | bond that joins amino acids |
| polypeptide | chain of 3+ amino acids |
| denaturation | when the bonds of a protein molecule are disrupted, causing temporary change in shape of the protein (and loss of function) |
| coagulation | bonds of a protein are disrupted, causing permanent change in shape |
| catalyst | a chemical that increases the rate of a reaction without altering the products or being used up itself |
| enzyme | a protein catalyst that allows chemical reactions to occur at low temperatures in the body |
| substrate | the molecule on which an enzyme works |
| active site | the area of the enzyme that combines with the substrate |
| cofactor | an inorganic ion that helps an enzyme combine with a substrate |
| coenzyme | an organic molecule synthesized from a vitamin that helps an enzyme to combine with a substrate molecule |
| competitive inhibitor | a molecule with a shape that is complimentary to a specific enzyme - it competes with the substrate for access to the active site and blocks chemical reactions |
| precursor activity | the activation of the last enzyme in a metabolic pathway by the initial substrate |
| allosteric activity | change in an enzyme's shape by binding of a molecule |
| amylase | an enzyme that breaks down carbohydrates - in saliva |
| peristalsis | rhythmic, wavelike contractions of muscle that move food along the gastrointestinal tract (involuntary) |
| sphincter | a constrictor muscle that regulates the opening and closing of a tubelike structure |
| mucus | protective lubricating substance composed mostly of protein |
| pepsin | a protein-digesting enzyme produced in the stomach |
| ulcer | a lesion on the surface of an organ |
| duodenum | the first segment of the small intestine |
| villi | small, fingerlike projections that extend into the small intestine to increase surface area for absoption |
| microvilli | microscopic, fingerlike projections of the cell membrane |
| capillary | a blood vessel that connects arteries and veins; the site of fluid and gas exchange |
| bile salt | a component of bile that breaks down large fat globules |
| gallstones | crystals of bile salts that form in the gallbladder |
