Which of the following types of molecular interactions play a role in protein folding? Select all that apply. A. Covalent bonds   B. Hydrogen bonds   C. Van der Waals attraction   D. Hydrophobic interactions

In the alpha-helices, which of the following statement is NOT true?   a.   Backbone carbonyl oxygen of residue (i) hydrogen bonds to backbone NH of the fourth residue of chain of residue (i + 4).   b.   Side chains project out from an α-helix.   c.   Hydrogen bonds are almost straight and parallel to the helix axis.   d.   Helix has a macrodipole.   e.   The rise or advance per amino acid residue is 0.54 nm.

The largest number of amino acids found in proteins are ________ A. Polar B.hydrophobic C.hydrophilic meaning that they tend to be _______ water. A. Attracted to B. Repelled from

All 20 amino acids found in human proteins have a common structure that includes:   A. An amino group (-NH2)   B. A carboxyl group (-COOH)   C. An R group   D. A and B   E. A, B, and C

1. Is there more than one way to fold a protein, given the conflicting demands of the different "R" groups and the protein existing in a watery environment? 2. Explain what an R group is. 3. Compare the backbone of a polypeptide with that of a nucleic acid. 4. Proteins perform critical functions in all of our cells. Without proteins, life wouldn’t exist. Think of some specific proteins and describe what function they perform.  5. Explain the difference between secondary and tertiary protein structures.

Identify which of the following amino acid residues can have hydrogen bonding between their side chain and the protein backbone. a. Tyrosine b. Alanine C. Leucine d. Asparagine Draw a picture showing the details of the hydrogen bonding between the side chain and the protein backbone for any amino acid residues from exercise 4 that are capable.

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

How does knowledges of protein structure help us to predict the function of unknown proteins?

Which of the following statements concerning SDS in SDS-PAGE is INCORRECT? a. SDS is a negatively charged detergent b. SDS can give all proteins a uniform charge c. the full name of SDS is sodium dodecyl sulfate d. SDS make protein gel electrophoresis to separate proteins based on molecular weight as well as protein surface charges e. SDS can denature proteins

Which of the following describes the most likely outcome of a mutation that causes a sin- gle amino acid to be removed from a protein subunit? A It will affect the primary, secondary, and tertiary structures of the protein. B с D It will affect the secondary and tertiary structures of the protein but not the primary structure. There will be no observable effect on the structure of the protein. It will change the primary structure of the protein without affecting other structures in the protein.