The spleen contains lymphocytes and another kind of white blood cell called macrophages that engulf and destroy bacteria, dead tissue, and foreign matter and remove them from the blood passing through the spleen.
The lymphatic system is a network of very small tubes or vessels that drain lymph fluid from all over the body.
The major parts of the lymph tissue are located in the bone marrow, spleen, thymus gland, lymph nodes, and the tonsils. The heart, lungs, intestines, liver, and skin also contain lymphatic tissue. One of the major lymphatic vessels is the thoracic duct, which begins near the lower part of the spine and collects lymph from the pelvis, abdomen, and lower chest.
The thoracic duct runs up through the chest and empties into the blood through a large vein near the left side of the neck. The right lymphatic duct is the other major lymphatic vessel and collects lymph from the right side of the neck, chest, and arm, and empties into a large vein near the right side of the neck.
Lymph nodes are round or kidney-shaped. Most lymph nodes are about 1 cm in diameter but they can vary in size. Most of the lymph nodes are found in clusters in the neck, armpit, and groin area. Nodes are also located along the lymphatic pathways in the chest, abdomen, and pelvis, where they filter the blood. Inside the lymph nodes, lymphocytes called T-cells and B-cells help the body fight infection. Lymphatic tissue is also scattered throughout the body in different major organs and in and around the gastrointestinal tract.
The spleen helps control the amount of blood and blood cells that circulate through the body and helps destroy damaged cells.
Lymph fluid drains into lymph capillaries, which are tiny vessels. The fluid is then pushed along when a person breathes or the muscles contract. The lymph capillaries are very thin, and they have many tiny openings that allow gases, water, and nutrients to pass through to the surrounding cells, nourishing them and taking away waste products. When lymph fluid leaks through in this way it is called interstitial fluid. Lymph vessels collect the interstitial fluid and then return it to the bloodstream by emptying it into large veins in the upper chest, near the neck.
Lymph fluid enters the lymph nodes, where macrophages fight off foreign bodies like bacteria, removing them from the bloodstream.
After these substances have been filtered out, the lymph fluid leaves the lymph nodes and returns to the veins, where it re-enters the bloodstream. Larger text size Large text size Regular text size. What Are the Spleen and Lymphatic System? What Does the Spleen Do? The body also uses the spleen as a place to store blood and iron for future use.
What Does the Lymphatic System Do? The major parts of the lymph tissue are located in the: bone marrow spleen thymus gland lymph nodes tonsils The heart, lungs, intestines, liver, and skin also contain lymphatic tissue. The major lymphatic vessels are: the thoracic duct: It begins near the lower part of the spine and collects lymph from the pelvis, abdomen, and lower chest.
The thoracic duct runs up through the chest and empties into the blood through a large vein near the left side of the neck.
There are around of these which mostly occur in the neck, thorax, abdomen and pelvis. They contain B- and T-cells, which mostly enter the nodes via the blood stream, and also contains macrophages. More information about lymph nodes. Tissue fluid is filtered by non-encapsulated or partially encapsulated aggregations of lymphoid tissue sometimes called Mucosa Associated Lymphoid Tissue MALT.
They are usually small, around 1mm in diameter, with the exceptions beting the tonsils , peyers patches and the appendix. These lymphoid aggregations are frequently found close to moist epithelial surfaces e.
Although the epithelia of these tissues has mechanisms to keep bacteria etc out of the body, this is not foolproof. Thus the lymphoid cells in these areas are able to respond to any bacteria or micro-organisms that do get through the epithelia. Activated B-cells in these areas can develop into plasma cells, and produce antibodies, in situ.
Lymphocytes from the larger permanent organs such as the tonsils are able to patrol the surrounding tissue, and quickly respond to foreign antigens. Like the lymph nodes, it also has a hilus hilium which is where the major blood vessels enter and leave. Like the thymus, it only has efferent lymph vessels, which leave from the hilium, and it does not have afferent lymph.
This eMicroscope is a section through part of the spleen. Can you identify the germinal centres, white and red pulp, arterioles, other blood vessels and the capsule. This image may also be viewed with the Zoomify viewer.
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