Prelude to the First Battle of Bull Run (Manassas). By July 1861, two months after Confederate troops opened fire on Fort Sumter to begin the Civil War, the northern press and public were eager for the Union Army to make an advance on Richmond ahead of the planned meeting of the Confederate Congress there on July 20.mpact of Bull Run (Manassas). Despite their victory, Confederate troops were far too disorganized to press their advantage and pursue the retreating Yankees, who reached Washington by July 22.
Bone Marrow. The bone marrow gives rise to all of the cells engaged in the defense mechanisms of the body (with minor exceptions). In babies it is found in all the bones, but moving through puberty it is replaced in the long bones by fat so that in adults it is found only in the central bones, such as the ischium.The key cells in bone marrow are the hematopoietic stem cells, which give rise to the lymphoid stem cells and the myeloid stem cells.But we put off red blood cells until the spring.). 1  Lymphocytes. 2  Lymphocytes are the only cells capable of adaptively (specifically) making the molecules (antibodies and T cell receptors) that specifically recognize antigens, which are molecules foreign to the body.
BONE MARROW: All the cells of the immune system are initially derived from the bone marrow through a process called hematopoiesis. During foetal development hematopoiesis occurs initially in yolk sac and para-aortic mesenchyme and later in the liver and spleen.This function is taken over gradually by the bone marrow.ymphoreticular cells include reticuloendothelial cells and lymphoid cells. Reticuloendothelial system: The reticuloendothelial system mainly comprise of phagocytic cells whose function is to engulf microbes, immune complex from blood and tissues and participate in inflammation.