BIO 121 Lecture Notes - Memory T Cell, Lymphatic Vessel, Thoracic Duct
18 Nov 2013
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Causes differentiation of lymphocytes resulting in: t cells, b cells, and nk cells. Secondary lymphoid structure (lymph nodes and tonsils) (most immune responses originate here) Consists of lymphocytes and more b cells to battle infectious agents. Provides an alternative route for the transport of: hormones, nutrients, waste products. Comparisons to the vascular capillaries: lymphatic capillaries are larger in diameter, lymphatic capillaries have thinner walls, lymphatic capillaries have an irregular outline. Comparisons to the vascular capillaries: lymphatic capillaries have anchoring filaments that connect to the surrounding connective tissue to keep the capillaries open, lymphatic capillaries have greater permeability. Lymphatic vessels do not have easily identifiable tunics (layers) Larger lymphatic vessels have valves just like most veins have. The thoracic duct collects lymph from tissues inferior to the diaphragm and from the left side of the upper body. The right lymphatic duct drains the right half of the body superior to the diaphragm.
