ANATOMY 1 Lecture Notes - Lecture 19: Lymphatic Vessel, Bone Marrow, Dendritic Cell
Document Summary
Sites where stem cells divide + become immunocompetent. = capable of mounting an immune response. Red bone marrow thymus in flat bones + epiphyses of some long bones. Bilobed organ in mediastinum between sternum + aorta trabeculae (extension of the capsule) divide two lobes into lobules lobules. Cortex = t cells, dendritic cells, epithelial cells, Medulla = mature t cells, epithelial cells, dendritic cells, macrophages macrophages thymic corpuscules. Clusters of epithelial cells that become arranged in concentric layers of flat cells that degenerate + become filled w/ keratohyalin granules + keratin. W/ age lymphoid tissue of thymus is replaced by fatty infiltrations => functional portion of gland is reduced considerably. All lymph flows through multiple lymph nodes on its path through lymph vessels. Filter lymph foreign substances are trapped by its reticular fibers. Located along lymphatic vessels, usually in groups. Stroma = capsule, trabecular, reticular fibers, + fibroblasts of a large group near mammary glands + groin lymph node.
