Antibodies protect against substances prior to cell infection. Antibodies are produced by a type of white blood cell called a B cell (B lymphocyte). B cells develop from stem cells in bone marrow. When B cells become activated due to the presence of a particular antigen, they develop into cells called plasma cells.ntibodies recognize specific antigens by identifying certain areas on the surface of the antigen known as antigenic determinants. Once the specific antigenic determinant is recognized, the antibody will bind to the determinant.
The Underground Railroad. For the 240 years from the first African slave until 1860, slaves ran and some escaped to freedom. In 1850, the value of a trained slave was around $2500 - an enormous sum at a time more than ten times the average person's annual earnings.
A well-organized network of people, who worked together in secret, ran the Underground Railroad. The work of the Underground Railroad resulted in freedom for many men, women, and children.It also helped undermine the institution of slavery, which was finally ended in the United States during the Civil War.Many slaveholders were so angry at the success of the Underground Railroad that they grew to hate the North.he Underground Railroad provided hiding places, food, and often transportation for the fugitives who were trying to escape slavery. Along the way, people also provided directions for the safest way to get further north on the dangerous journey to freedom.