The relative molecular masses of the two amino acids other than glycine in glutathione are 121.0 g mol and 147.0 g mol1. Using the information provided above, determine the molar mass of the tripeptide.

(a) How many tripeptides can be made from glycine, alanine, and leucine, using each amino acid only once per tripeptide? (b) Write the structural formulas of these tripeptides and name them in the shorthand abbreviation used for showing amino acid sequences.

Which of the following are true concerning the chemical bond that forms between the carboxyl (RCOOH) group of one amino acid and the amino (RCNH2) group of another? a.The bond is called a peptide bond. b.It is formed by inserting a water molecule between them. c.It is formed by a dehydration reaction. d.A polypeptide has more of these bonds than a protein.

For the tripeptide SerArgIle which amino acid residues a. are hydrophilic b. are hydrophobic c. possess polar neutral R groups d. participate in two amide linkages

Do the amino acid sequences: valine-asparagine and asparagine-valine represent the same compound? Explain.

Which of the following describes the primary structure of proteins? a. The collective shape assumed by all of the chains in a protein containing multiple chains. b. The folding of an individual protein molecule. c. The regular repeated shape of the protein molecules backbone. d. The sequence of amino acids bonded together by peptide bonds.

In a pleated sheet secondary structure for a protein a. describe the general shape of the protein backbone b. describe the general locations for the amino acid R groups

What characteristics indicate that amino acids exist as zwitterions?

22-49 Based on your knowledge of the chemical properties of amino acid side chains, suggest a substitution for leucine in the primary structure of a protein that would probably not change the character of the protein very much.

Fill in the blanks in the following statements: aThe order of the amino acids in a protein is the ______ structure of that protein. The _______ of the backbone chain of a protein is the secondary structure of that protein. The tertiary structure of a protein describes the ______ of the secondary structure. b Hydrogen bonding between the oxygen atoms of carbonyl groups and the hydrogen atoms of amide groups in the same protein chain gives the secondary structure, called the ______. c Hydrogen bonding between the oxygen atoms of carbonyl groups and the hydrogen atoms of amide groups in the adjacent protein chain gives the secondary structure, called the ______.