By choosing a tandem model, you will be less likely to outgrow your trailer; the extra upfront expense may be worth it in the long run. While towing level is not a factor for single axle models, level towing is a must for a tandem axle trailer. If the load is not level it can cause extra wear and tear on one set of axles, and reduce the life of your tires. The initial investment for a tandem trailer is higher than the cost for a single axle model.
The five primary classes of immunoglobulins are IgG, IgM, IgA, IgD and IgE. These are distinguished by the type of heavy chain found in the molecule.
Immunoglobulin G (IgG) is the most abundant circulating antibody, making up 80% of the total antibodies and 75% of that found in serum. It contains a single antibody protein complex, with two heavy chains and two light chains.igure 15.16 Different Antibody types. There are five different antibodies classes that are formed in the cell. See the text for more details. IgM is the largest antibody, with five Y structures being joined by their Fc regions in a circular configuration.