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.
Lymph organs include the bone marrow, lymph nodes, spleen, and thymus. Bone marrow contains tissue that produces lymphocytes. B-lymphocytes (B-cells) mature in the bone marrow. T-lymphocytes (T-cells) mature in the thymus gland.Other blood cells such as monocytes and leukocytes are produced in the bone marrow. Lymph nodes are areas of concentrated lymphocytes and macrophages along the lymphatic veins.ome lymphocytes migrate to the thymus and become T cells that circulate in the blood and are associated with the lymph nodes and spleen. B cells remain in the bone marrow and develop before moving into the circulatory and lymph systems. B cells produce antibodies. Macrophage Attacking E.coli (SEM x8,800).