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.
The side groups are what make each amino acid different from the others. Of the 20 side groups used to make proteins, there are two main groups: polar and non-polar. These names refer to the way the side groups, sometimes called R groups, interact with the environment. carboxyl group is made up of one carbon (C) and two oxygen (O) atoms. That carboxyl group has a negative charge, since it is a carboxylic acid (-COOH) that has lost its hydrogen (H) atom. What is left â the carboxyl group â is called a conjugate base. The second carbon is connected to the amino group.