A. No. i.Protein is made up of polypeptides. ii.Ex a sweater is made of yarn. 8.What is the basic structure of an amino acid? Why do different amino acids have distinct chemical properties? How are amino acids assembled to make polypeptides? Summarize the structural features of a polypeptide chain.A.Amino Acids: HYDROPHILLIC
i.Amino group ( NH2) and a carboxyl group ( COOH). ii.Center has alpha (a) carboniii.R Group is side chain that differs with each amino acid.1.Affects chemical properties 2.Nonpolar side chains: hydrophobic 3.Polar side chains are hydrophilic iv.Polypeptide is a linkage of many amino acids by a covalent peptide bond. 1.Each polypeptide has a unique sequence of amino acids 9.Describe the four levels of protein structure. What is the chemical basis of each? A. Primary i.Linear chain of amino acids, COVALENT BONDINGii.Determined by genesB. Secondary i.Coils and folds due to hydrogen bonds, backbone. HYDROGEN BONDING. ii.(a) helix: coil between every fourth amino acidiii.(b) sheet: two strands parallel. 1.Core of globular C. Tertiary i.Overall shape of pp due to interactions between side chains (R groups) of aa 1.HELD TOGETHER BY ALL FOUR WEAK INTERACTIONSii.Hydrophobic interaction: exclusion of non-polar substances by water molecules iii.Disulfide bridges: covalent bond where two cysteine (sulfhydryl -SH) monomers are brought together by folding. D. Quaternary i.Multiple polypeptides forming a functional protein 1.Ex: collagenii.HELD TOGETHER BY ALL FOUR WEAK INTERACTIONSE.ALL PROTIENS HAVE THREE OR FOUR LEVELS OF STRUCTURE10. What determines the conformationof a protein? How do variations in the environment influence a protein’s conformation? A.A polypeptide chain of a given amino acid sequence can spontaneously arrange itself into a 3D shape determined and maintained by the interactions responsible for secondary and tertiary structure. B.If the Ph, salt concentration, temperature are adjusted it will become destroyed aka denaturation. C.Transfer from an aqueous solution to a nonpolar solution such as ether or chloroform. D.Heat can also play a factor, denaturation can be reversed if denaturation properties areremoved. Nucleic Acids11. Define the following terms: nucleic acid, nucleotide, nucleoside (look it up!), purine, pyrimidine, mRNA, and ribosome.
A.Nucleic Acidi.Family of monomers constructed of polymers called nucleotides B. Nucleotidesi.Four different kindsii.Most complex monomer iii.Composed of a pentose sugar, phosphate, a nitrogenous base (ring shape)C. Nucleosidei.Portion of a nucleotide WITHOUT any phosphate groups D. Purinei.Six membered ring fused to a five membered ring ii.Adenine (A) and Guanine (G)E. Pyrimidine i.One six membered ring of carbon and nitrogen atoms. ii.Cytosine (CC) and Thymine (T) and Uricil (U) 1.Uricil in RNA F.C,A,G found in DNA and RNA i.T found only in dna ii.U found in RNA G. mRNA i.genetic information in the sequence of nucleotidesH. Ribosomei.Link amino acids together determined by mRNA.