Unit I

More documents

Recommendations

Info

Spleen (LP): ( Capsule - Trabeculae - Red and white pulp)Spleen (HP): (Arteriole - Lymphatic sheath - Sinusoids - Cords of Billroth)48
Spleen:The spleen is a blood filtering lymphoid organ. It is covered by a capsule consisting of a connectivetissue and smooth muscle fibres. The capsule sends extensions known as trabeculae into the substance ofspleen. The parenchyma of the spleen is arranged as red and white pulp The white pulp consists of lymphoidnodules with an eccentrically placed arteriole. These are called splenic corpuscles or Malphigian corpuscles.Red pulp consists of splenic cords of Bilroth which have linearly arranged groups of lymphocytes andmacrophages. Between the splenic cords are the sinusoids of spleen lined by discontinuous endothelium.The arteries branch in the trabeculae and then they enter the white pulp. Smaller trabeculae showonly the veins. In the white pulp the arteries are covered by reticular sheaths (not seen in the slide) whichare heavily the infiltrated with the lymphocytes. These are the lymphatic nodules, which may show thegerminal centre. White pulp is distributed along arteries that leave trabeculae. When a sheath is expandedto form the nodule, the artery gives off a branch to supply the nodule called follicular artery. A follicularartery leaves white pulp and enters the red pulp. Here it divides into 2 to 6 branches, which radiate indifferent directions. These are straight or penicillar arteries. Each of these again divides in to 2 to 3 arterioles.They enter curious little structures called as ellipsoids. Perivascular lymphatic sheaths of the arteries andarterioles are the thymus dependent zone of the spleen. The border between the red and white pulp is notsharp. This is the transitional or marginal zone.In the red pulp there are the sinusoids lined by long narrow endothelial cells showing slits. The redpulp between two sinusoids is like a cord so called Bilroth cords. The red pulp contains RBCs, WBCs,plasma cells, macrophages and reticular cells. The basic cells of the germinal centre are activated B cells.The rim that surrounds the centre is composed of the T cells. From this position the plasma cells movereadily into the red pulp.Notes:49
Page 4: Mitochondrion Golgi apparatusSmooth
Page 7 and 8: . Nonmembrane bound: These organell
Page 9 and 10: Nucleus: It is made up of deoxyribo
Page 11 and 12: Intercellular contactsThe plasma me
Page 13 and 14: 3. Epithelial tissueHuman body is m
Page 15: Compound epithelium: They have two
Page 18 and 19: 4. Connective tissueFibroblast. Fib
Page 20 and 21: Collagen fibres Elastic fibresLoose
Page 22: 5. Muscular TissueStriated muscle L
Page 25 and 26: Sarcomere (Relaxed): Each myofibril
Page 27 and 28: Smooth muscle (LP): Smooth muscle f
Page 30 and 31: Astrocyte (Fibrous) Astrocyte (Prot
Page 32: Peripheral nerve T.S: (Epineurium -
Page 35 and 36: 7. CartilageIt is a specialised con
Page 37 and 38: White fibrocartilage: It shows bund
Page 40 and 41: Decalcified bone T.S.: (Fibrous and
Page 42 and 43: 9. Blood VesselsElastic artery: (Tu
Page 44 and 45: VeinCapillaries: (Endothelium- Basa
Page 46 and 47: 10. Lymphoid TissueLymph node (LP):
Page 50 and 51: Thymus: (Capsule-Septa-Lobules-Cort
Page 52 and 53: Palatine Tonsil (LP): (Stratified s
Page 54 and 55: Morphological classification of exo
Page 56 and 57: Serous salivary gland e.g Parotid g
Page 58 and 59: Mucous salivary gland (LP): (Interl
Page 61 and 62: Mixed salivary gland (LP): A saliva
Page 63 and 64: 12. Integumentary SystemSkin, the l
Page 65 and 66: Hair: In humans, hairs are not impo
Page 67 and 68: Sebaceous gland: It is seen on the
Page 69: Tooth: The tooth shows a projected

Unit I

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?