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.
Chemically, an amino acid is a molecule that has a carboxylic acid group and an amine group that are each attached to a carbon atom called the Î± carbon. Each of the 20 amino acids has a specific side chain, known as an R group, that is also attached to the Î± carbon. The R groups have a variety of shapes, sizes, charges, and reactivities. This allows amino acids to be grouped according to the chemical properties of their side chains.