Unit 1, Chapter 5 Flashcards
macromolecules
a giant molecule formed by the joining of smaller molecules, usually by a dehydration reaction. polysaccharides, proteins, and nucleic acids are macromolecules
polymer
a long molecule consisting of many similar or identical monomers linked together by covalent bonds
monomers
the subunit that serves as the building block of a polymer
enzymes
a macromolecule serving as a catalyst, a chemical agent that increases the rate of a reaction without being consumed by the reaction. most enzymes are proteins
dehydration reaction
a chemical reaction in which two molecules become covalently bonded to each other with the removal of a water molecule
hydrolysis
a chemical reaction that breaks bonds between two molecules by the addition of water; functions in disassembly of polymers to monomers
carbohydrates
a sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides)
monosaccharides
the simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. also called simple sugars, monosaccharides have molecular formulas that are generally some multiple of CH2O
disaccharide
a double sugar, consisting of two monosaccharides joined by a glycosidic linkage formed by a dehydration reaction
glycosidic linkage
a covalent bond formed between two monosaccharides by a dehydration reaction
polysaccharides
a polymer of many monosaccharides, formed by dehydration reactions
starch
a storage polysaccharide in plants, consisting entirely of glucose monomers joined by glycosidic linkages
glycogen
an extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch
cellulose
a structural polysaccharide of plant cell walls, consisting of glucose monomers joined by b (beta) glycosidic linkages
chitin
a structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods
lipids
any of a group of large biological moelcules, including fats, phospholipids, and steroids, that mix poorly, if at all, with water
fat
a lipid consisting of three fatty acids linked to one glycerol molecules; also called a triacylglycerol or triglyceride
fatty acid
a carboxylic acid with a long carbon chain. fatty acids vary in length and in number and location of double bonds; three fatty acids linked to a glycerol molecule form a fat molecule, also called a triacylglycerol or triglyceride
triacylglycerol
a lipid consisting of three fatty acids linked to one glycerol molecules; also called a fat or triglyceride