Melinda Rodriguez pre-lecture A&P2 Dr. I
Chapter 20 – Lymphatics
-Describe the composition of lymph
Lymph means clear water, lymph is comprised of interstitial fluid within a lymphatic vessel.
-State three functions of lymph
1. return excess tissue fluid to the blood.
2. return excess proteins to the blood
3. Carry absorbed fat from the intestines to the blood.
-Describe the direction of flow of lymph through the lymphatic system
Lymphatic capillaries - collecting lymphatic vessels - lymphatic trunks -lymphatic ducts.
-Name those regions of the body drained by the right lymphatic duct
The right upper limb, the right side of the head, and the R. thorax to R. subclavian vein.
-Name those regions of the body drained by the thoracic duct
The rest of the body including 2 large lumbar trunks that drain the lower limbs & the
intestinal trunk to the L. subclavian vein.
-Describe those mechanisms that assist in lymph transport
Pulsations of nearby arteries, contractions of skeletal muscle and smooth muscle in the
vessel walls.
-Name lymphoid cells and their functions
Lymphocytes 2 types
T cells -manage immune response, by attacking/ destroying infected cells.
B cell – protects the body by producing plasma cells that secrete antibodies.
Macrophages- phagocytize foreign substances and activates T cells
Dendritic cells- capture antigens (Ag) and bring to lymph nodes
Reticular cells- produce fibrous stroma to support other cells.
-Describe location, structure, and function of lymph nodes
Lymph nodes filter lymph and activate immune response, Cervical nodes are in the neck,
Axillary nodes are in the axilla region, and inguinal nodes are situated in the groin area,
Lymphatic vessels are also clustered throughout the body. Lymph nodes are surrounded by a
dense fibrous capsule that has trabeculae that extend inward dividing the node, a cortex that
houses T cells in transit, Medulla, and medullary cords (inward extension of cortical lymphoid
tissue) B & T cells found here.
-Describe structure and function of the spleen, thymus, tonsils, and Peyer’s patches
