Biology 320 Exam 1 questions and answers

Dehydration Small molecules combine to form larger ones. For example: sugar monomers combine to form starch polymers Hydrolysis One larger molecule is split by the addition of H+ and OH- (from water) to the components Polymers large chains of identical molecular units strung together Monomers the units that serve as the building blocks of polymers Another name for a dehydration reaction is... condensation reaction Cells contain ___ major families of small organic molecules four The four major families of small organic molecules are: 1. Carbohydrates 2. Fatty Acid 3. Amino acids 4. Nucleotides The simplest carbohydrate is... A monosaccharide, one sugar unit ____ is a primary energy source and precursor of many organic molecules Glucose (six- carbon backbone) Two monosaccharides linked together make a disaccharide such as ... Sucrose Glucose + fructose = Sucrose Glucose + glucose = Maltose How do Americans get most of their sugar? HFCS (high fructose corn syrup) What are two examples of digestive enzyme deficiencies? Lactose intolerance and sucrase-isomaltase complex deficiency sucrase-isomaltase complex deficiency intolerance of ingested sucrose 2% of Americans are heterozygous for this disorder Treatment includes the dietary restriction of sucrose, and enzyme replacement therapy. A polysaccharide consists of ... many sugar units (same or different) covalently linked. The most common polysaccharides are: chains of glucose: 1. starch 2. glycogen 3. cellulose Starch energy storage in plants made of glucose units Glycogen storage form of glucose found in animal tissues Cellulose major component of plant cell walls made of glucose units, but in different bonding arrangements then in starch Difference between cellulose and starch- glucose linkage is flipped around from alpha to beta Comparison between glycogen and starch Glycogen is much more branched than starch, but glycosylic linkage is the same A fatty acid has two chemically distinct regions: long hydrocarbon chain (hydrophobic) and carboxyl group (acid) Fatty acids are amphipathic amphipathic having both a hydrophilic region and a hydrophobic region Palmitic acid is an example of a .... Fatty acid molecule Fatty acids serve as... A concentrated food reserve in calles How are fatty acids stored? triacylglycerol molecules examples of triglycerides are butter, lards, oils Triglycerides are rich sources of energy Triglycerides have ___ fatty acid tails attached to a molecule of glycerol three Do triglycerides or carbohydrates yield more energy on a per weight basis? Triglycerides (more than twice as much) Unsaturated fatty acids are ______ at room temperature Liquids (oil) One or more double bonds between the carbons in the tails permit kinks Saturated fatty acids have ________ C-C bonds in the tails and are ________ at room temperatures only single solid the process of ______________ (taking a polyunsaturated fat and forcing hydrogens onto it to saturate it) forms what are called ________________ hydrogenation trans fats the most important function of fatty acids in cell is the formation of membranes. they are composed largely of ... phospholipids The membrane- property of phospholipids results from their ___________ nature amphipathic Phospholipids have the same structure as triglycerides except for ____________ remove fatty acid and link phosphate group A ___________ is a polymer constructed from amino acid monomers. protein All proteins are constructed from ____ kinds of amino acids 20 An amino acid consists of a central carbon atom bonded to four covalent partners Three of these four covalent partners are common to all 20 amino acids: a carboxyl group, an amino group, and a hydrogen atom The fourth covalent of an amino acid is variable and gives that amino acids its special chemical behavior and is called the ... Side group