Question

Ramachandran Plot maps:

• A. pH Vs Charge
• B. Radius Vs Mass
• C. Allowed \(\phi-\psi\) dihedral angles
• D. Bond energies

Hint:

Ramachandran plot is used for protein backbone analysis and maps allowed \(\phi\) and \(\psi\) dihedral angles.

Answer 1

The Correct Option is C

Concept:
Ramachandran plot is an important tool used in protein structure analysis. It shows the allowed and disallowed conformations of amino acid residues in a protein.

Step 1: Understand protein backbone angles.
In a polypeptide chain, each amino acid residue has two important backbone dihedral angles: \[ \phi = \text{phi angle} \] \[ \psi = \text{psi angle} \]

Step 2: Meaning of Ramachandran plot.
The Ramachandran plot maps possible values of \(\phi\) and \(\psi\) angles. Some combinations are allowed because they do not cause steric clashes, while others are not allowed.

Step 3: Use of Ramachandran plot.
It is used to check the quality of protein structure and to understand whether a protein conformation is sterically possible.

Step 4: Select the correct option.
Since Ramachandran plot represents allowed \(\phi-\psi\) dihedral angles, option (C) is correct. \[ \therefore \text{Correct Answer is (C)} \]