Your friend comes to you with a problem. It seems his shrimp boats aren’t catching nearly as much shrimp as they used to. He can’t understand why because originally he caught all the shrimp he could handle. Each year he added a  new  boat,  and  for  a  long  time  each  boat  caught  tons  of  shrimp.  As  he  added  more  boats,  there  came  a  time when each boat caught somewhat fewer shrimp, and now, each boat is catching a lot less shrimp. Which of the following topics might help your friend understand the source of his problem?

#Question id: 731

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following structure is mentioned in the given Ramachandran plot

#Question id: 732

#Unit 1. Molecules and their Interaction Relevant to Biology

Ramachandran plots can help increase the accuracy of models derived from x-ray crystallography data. The plot below was created by measuring phi, and psi for each amino acid residue in a 2.2 A resolution crystal structure. In the plot, which excludes Gly and Pro residues, selected residues (dots) are numbered 1 through 5.

Which of the following statements can be correctly stated for this plot in reference to selected residues?

A. Residues 1 and 3 are in either B sheets

B. residue 2 is in a right-handed a helix, and residue 4 is in a left-handed a helix.

C. If residue 5 were Gly, it might be in an acceptable position in the plot

#Question id: 733

#Unit 1. Molecules and their Interaction Relevant to Biology

Which one of the statements on protein conformation, detailed below is INCORRECT?

#Question id: 734

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statements is true for two different tripeptides consisting of either glycine or proline?

#Question id: 735

#Unit 1. Molecules and their Interaction Relevant to Biology

The a-keratin chains indicated by the diagram below have undergone one chemical step. To alter the shape of the a-keratin chains—as in hair waving—what subsequent steps are required?

#Question id: 736

#Unit 1. Molecules and their Interaction Relevant to Biology

The most important contribution to the stability of a protein’s conformation appears to be the: