In extracellular proteins the amino acid Cys can interact with another Cys to form a bond sometimes called _______. The formation of this covalent bond is reaction. a. O b. disulfide, cystine, oxidizing O c. disulfide, cysteine, reducing d. disulfide, cystine, dehydration e. peptide, polypeptide, oxidizing peptide, polypeptide, condensation

Which of the following amino acid or types of amino acids are are rarely found in beta sheets? a. Polar charged amino acids  b. Polar uncharged amino acids  c. Non polar amino acids  D. Glycine

Which of the following is incorrect about the beta-sheet? a. The strands in anti-parallel beta-sheets are usually connected with turns b. Side chains are alternated above and below the sheet C. Parallel beta-sheets are less stable than the anti-parallel ones Od. It is stabilized by hydrophobic interactions between the side chains of nonpolar residues

The following are functions of lipids EXCEPT A. Isolate cellular components from its environment B. Serve as signal molecules and mediators of cellular processes C. Membrane fluidity determinant D. Alternative energy source of cells O E. Facilitate movement of metabolites in and out of cells

Which of the following is incorrect about the peptide Arg-Asp-Cys-Tyr-Gln-Arg-Glu? It has six peptide bonds b. It has a net charge of zero at pH 7 It has six charged groups at pH 7 d. None; all the other choices are correct a. C.

How would adding acid to a non-buffered solution be most likely to affect protein structure? Select one: a. Adding acid would disrupt the primary structure of the protein b. Adding acid would cause the protein to become a lipid c. Adding acid would cause the protein to become a carbohydrate d. Adding acid would disrupt the secondary and tertiary structure of the protein

An allosteric interaction between a ligand and a protein is one in which: a. binding of a molecule to a binding site affects binding of additional molecules to the same site. b. binding of a molecule to a binding site affects binding properties of another site on the protein. c. binding of the ligand to the protein is covalent. d. multiple molecules of the same ligand can bind to the same binding site. e. two different ligands can bind to the same binding site.