FTP, identify this diagram that maps out the conformations available to a polypeptide and is named for its Indian constructor.
The x- and y-axes of this construct are the torsional angles about the alpha-carbon to nitrogen bond and alpha-carbon to carbon bond, respectively.  Actually toroidal in shape, the structure of collagen is found in its upper-left quadrant, while a right-handed 310 ["three-sub-ten"] helix is located in the lower left.  The lower right quadrant is usually forbidden, except for those polypeptides containing many glycine residues.  FTP, identify this diagram that maps out the conformations available to a polypeptide and is named for its Indian constructor.
The x- and y-axes of this construct are the torsional angles about the alpha-carbon to nitrogen bond and alpha-carbon to carbon bond, respectively.  
Ramachandran diagram