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.
Examples of beta globulins include a protein that binds iron in the body, factors involved with the immune targeting of foreign material for immune destruction, and a species of immunoglobulin antibody termed IgM. Gamma globulins are manufactured in cells of the immune system known as lymphocytes and plasma cells.