Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. In eudicots, pith is located in the center of the stem. In monocots, it extends also into flowering stems and roots. The pith is encircled by a ring of xylem; the xylem, in turn, is encircled by a ring of phloem.
Throughout the lymph node's interior are a series of street-like channels called sinuses that help guide the flow of lymph from the afferent lymphatic vessels, through the cortex and medulla, and finally to the efferent lymphatic vessels at the hilum.ach lymph node chain is responsible for draining a particular body region or structure. For example, the lymph node chains in your armpits drain your arms and upper chest, while the chains in your groin are responsible for filtering lymph from your feet, legs, genitals, and lower abdominal wall.
Posterior lymph nodes are located along the back of the neck. Deep cervical lymph nodes are associated with their positions adjacent to the internal jugular vein, which runs near the sides of the neck. They are known as the lateral jugular, anterior jugular, and jugulo-digastric lymph nodes.The inferior deep cervical lymph nodes, the juguloomohyoid nodes, and the supraclavicular, or scalene, nodes are considered deep jugular nodes.here are some 600 to 700 lymph nodes scattered throughout the body. Cervical lymph nodes are located in the neck region. There are two general categories of cervical lymph nodes: anterior and posterior.