Exam 14: Proteins

Lysine is a weak acid under physiological conditions but it is classified as a basic amino acid. Briefly explain.

The following is an example of a secondary protein structure.

What type of interaction would occur between the side chains of the two amino acids shown below?

Which of the following is the form that human body uses to excrete nitrogen?

Consider the structure shown below. Fill in the blanks with an integer (1,2,3,4,5....)as shown in the diagram or to represent a specified number. -This structure contains _______________________ peptide groups.

Consider the structure shown below. Fill in the blanks with an integer (1,2,3,4,5....)as shown in the diagram or to represent a specified number. -The atom represented by the number _______________________ would carry a δ- charge.

Consider a protein at 25 °C which is heated to 48 °C then cooled back to 25 °C. The following shows schematically the protein structure at these three temperatures, respectively. 25 °C 48 °C 25 °C Based on this information, the enzyme activity will return at the final temperature (25 °C).

Consider the following representation of an enzyme-catalyzed reaction. This image could represent the reaction in which lactase catalyzes the hydrolysis of lactose (a disaccharide)into glucose and galactose (two monosaccharides). Fill in the blanks with the appropriate letter (A,B,C,D,....)from the image. -An effector would bind at ______________________.

The following representation accurately depicts the structure of a peptide group.

Consider the level of protein structure that forms when the two polypeptides shown below interact. Which type of side chain interaction is particularly important in forming this level of structure?

Consider the structure shown below. Fill in the blanks with an integer (1,2,3,4,5....)as shown in the diagram or to represent a specified number. -The N-terminal group is represented by the number___________________,

Draw the zwitterion ion form of phenylalanine.

The amino acid shown below maybe associated with ALS (Lou Gehrig's disease) and Parkinson's disease. Which of the following is the form of this amino acid at a physiological pH?

When the term "essential" is applied to a substance, this means that it cannot be synthesized by an organism and must be obtained from dietary sources.

What type of interaction would occur between the side chains of two molecules of the amino acid shown below?

How many chiral carbon atoms are present in the amino acid shown below?

Which of the following contains a sulfur atom as part of the side chain?

Draw the structure of a tripeptide that has a C-terminal alanine, an N-terminal serine and an leucine. Indicate the backbone in the structure.

Which of the following must be supplied by the diet?

Consider the structure shown below. Fill in the blanks with an integer (1,2,3,4,5....)as shown in the diagram or to represent a specified number. -The backbone contains ______________________ amino acids.