FCS 102 Exam 2 Study Guide Chapter 5 Proteins Terms Amino acids Main building block of a protein Peptide bonds A chemical bond that joins amino acids Condensation reactions chemical process by which 2 molecules are joined together to make a larger more complex molecule with the loss of water Hydrolysis reactions A large molecule is split into smaller sections by breaking a bond adding H to one section and OH to the other Amine group Nitrogen containing component of an amino acid Polypeptide Proteins that have more than 12 amino acids Denaturation the alteration of a proteins three dimensional structure by head acid chemicals enzymes or agitation Transamination the process whereby an amino group is formed via the transfer of an amino group from one amino acid to another organic compound Pepsinogen the inactive form proenzyme of pepsin produced in the stomach Pepsin an enzyme needed for protein digestion Urea a relatively nontoxic nitrogen containing compound that is produced from ammonia Vegan a type of vegetarian who consumes no animal products Lacto ovo vegetarians a type of vegetarian who consumes dairy products and eggs in an otherwise plant based diet Lactovegetarians a type of vegetarian who consumes dairy products but not eggs in an otherwise plant based diet Marasmus a form of PEM characterized by extreme wasting of muscle and adipose tissue Kwashiorkor a form of PEM often characterized by edema in the extremities Basic structure of amino acids central carbon bond of a hydrogen amino group NH2 carboxylic acid COOH Basic structure of proteins primary secondary tertiary quaternary prosthetic groups Essential amino acids Essential amino acids cannot be made by the body As a result they must come from food The nine essential amino acids are histidine isoleucine leucine lysine methionine phenylalanine threonine tryptophan and valine Nonessential amino acids Nonessential means that our bodies produce an amino acid even if we don t get it from the food we eat They include alanine asparagine aspartic acid and glutamic acid Conditionally essential amino acids Conditional amino acids are usually not essential except in times of illness and stress They include arginine cysteine glutamine tyrosine glycine ornithine proline and serine Complete proteins A complete protein contains an adequate amount of all of the essential amino acids that should be incorporated into a diet Include Meat Fish Poultry Cheese Eggs Yogurt and Milk Incomplete proteins An incomplete protein is any protein that lacks one or more essential amino acids in correct proportions Even if the protein contains all the essential amino acids they must be in equal proportions in order to be considered complete Include Grains Nuts Beans Seeds Peas Corn Complementary proteins By combining foods from two or more incomplete proteins a complete protein can be created The amino acids that may be missing from one type of food can be compensated by adding a protein that contains that missing amino acid When eaten in combination at the same meal you are providing your body with all the essential amino acids it requires Includes Grains with Legumes Nuts with Legumes Grains with Dairy Dairy with Seeds Legumes with Seeds Limiting amino acids an essential amino acid or indispensable amino acid that can t be synthesized by the organism Non essential ones are a little confusing as some can be made from others The sulfur containing acids methionine and homocysteine can be converted into each other but neither can be synthesized on its own The recommended daily amounts for children age three and up is approximately 10 20 higher than adult levels and levels in infants can be as much as 150 higher in the first year Protein quality how well a protein from food matches the body s requirements and therefore how useful the protein is for our body This is determined by looking at the building blocks which make up the protein called Amino Acids Protein sources seafood white meat poultry milk cheese yogurt eggs and beans Protein functions repair and maintenance energy supply hormones and enzymes transportation and storage of molecules and antibodies Nitrogen balance the condition in which protein intake equals protein loss by the body Negative nitrogen balance the condition in which protein intake is less than protein loss by the body Positive nitrogen balance the condition in which protein intake is greater than protein loss by the body Amino acid breakdown The carbon skeletons of amino acids are broken down into metabolites that can either be oxidized into CO2 and H2O to generate ATP or can be used for gluconeogenesis Excretion of urea The liver turns ammonia into urea and then urea is removed through urine Protein digestion Two of the substances secreted by the stomach HCl and pepsinogen interact to create pepsin an enzyme that plays a very important role in protein digestion The process that takes place when proteins are disintegrated by the enzymes is called hydrolysis Protein absorption 50 percent of the digested protein between the stomach and the jejunum middle section of the small intestine 90 percent when the digested food gets in the ileum final segment of the small intestine Chapter 6 Lipids Terms Fats a type of lipid that is solid at room temperature Oils a lipid that is liquid at room temperature Hydrophilic having a tendency to mix with dissolve in or be wetted by water Hydrophobic will ride to the top because less dense than water and separate from water Fatty acids a type of lipid consisting of a chain of carbons with a methyl group on one end and a carboxylic acid group on the other Triglyceride an ester formed from glycerol and three fatty acid groups Triglycerides are the main constituents of natural fats and oils and high concentrations in the blood indicate an elevated risk of stroke Ester linkage Esters are chemical compounds consisting of a carbonyl adjacent to an ether linkage They are derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol Phospholipid a lipid containing a phosphate group in its molecule Monounsaturated fatty acids a fatty acid that contains one carbon carbon double bond in its backbone Polyunsaturated fatty acids a fatty acid that contains more than one carbon carbon double bond in its backbone Hydrogenation a reduction reaction which results in an addition of hydrogen usually as H2 If an organic compound is hydrogenated it becomes more saturated Glycerol It is a colorless