The average estimated cash rent was $202 per acre on top quality land, $161 per acre on average quality land, and $124 per acre on poor quality land. This was an increase in rental rates of 2.0% for top quality land, 1.9% for average quality land, and 2.5% for poor quality land.
R-Group. In solution it is the nature of the amino acid R-groups that dictate structure-function relationships of peptides and proteins.
Principles of Biochemistry/Amino acids and proteins. Amino acids are molecules containing an amine group(NH2), a carboxylic acid group(R-C=O-OH) and a side-chain( usually denoted as R) that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen.