By definition, basalt is an aphanitic igneous rock with less than 20% quartz and less than 10% feldspathoid by volume, and where at least 65% of the feldspar is in the form of plagioclase. Basalt features a glassy matrix interspersed with minerals.The average density is 3.0 gm/cm 3.y definition, basalt is an aphanitic igneous rock with less than 20% quartz and less than 10% feldspathoid by volume, and where at least 65% of the feldspar is in the form of plagioclase. Basalt features a glassy matrix interspersed with minerals.
An antigen is defined as a substance that reacts with antibody molecules and antigen receptors on lymphocytes. 2. An immunogen is an antigen that is recognized by the body as non-self and stimulates an adaptive immune response. 3. Chemically, antigens are large molecular weight proteins and polysaccharides. 4.
Antigens and the Immune System. When antigens enter the body, the immune system alarm is triggered. The first line of defense is for the B-lymphocytes, or B cells, to be sent out. These are special leukocytes, also called white blood cells. Their job is to tag the antigen so that the correct response can be made.