Tonsils

  • Tonsils are lymphoid tissues encircling the pharynx.tonsils
  • These are secondary lymphoid tissues.
  • They are very similar to Thymus internal structure.
  • There are 3 types of tonsils palatine tonsils, lingual tonsils and pharyngeal tonsils.
  • The tonsils also setup resistance to infection microbes.
  • The tonsils sample the microbes in the inhaled air form suitable antibiotics.

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Bone marrow

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Thymus

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The thymus is a flat, bi-lobed organ situated above the heart. Immature T-cells are simply referred as "Thymocyte", these are densely packed outer compartment (or) cortex of the thymus lobule. Some of the thymic epithelial cells in the outer cortex, called "nurse cells", have long membrane extensions that surround as many as so thymocytes, forming large multicellular complexes The average weight of the thymus is 70 grams in infants; its age dependent involution levels an organ with an average weight of only 3 grams in the elderly. Explanations about Thymus: The thymus covered by a fibrous capsule . It is formed of two lobes. Each lobe of the thymus is organized into lobule which is separated from one another by septa called trabeculae. With in each lobule, the cells are arranged into an outer cortex and an inner medulla. The cortex is tightly packed with proliferating immature lymphocytes while the medulla contains more mature cells. As ...
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