biol320-lab 8

what are the two major groups of lymphatic structures occur in connective tissues?

encapsulated lymph organs and diffuse lymphoid organs

what do the encapsulated lymph organs have?

lymph nodes, thymus gland, spleen

which has a defined boundary that separates them from a connective tissue: encapsulated lymph organ or diffuse lymphoid organ? what is this boundary?

encapsulated organ; fibrous capsule

what is encased in a dense connective tissue capsule, are scattered throughout the lymphatic system with a high concentration in the upper limbs and in the axillary and cervical regions?

lymph nodes

what is the largest encapsulated lymphatic organ in the body, located lateral to the stomach, located on left upper side of abdominal cavity below the diaphragm?

spleen

what surrounds the spleen and protects the underlying tissue of red and white pulp?

capsule

the color of the red pulp of the spleen is due to?

blood that filters through

the color of the white pulp of the spleen is due to?

appears blue due to the lymphocyte nuclei stains

red or white pulp of spleen: free and fixed phagocytes in the pulp remove abnormal RBC and other antigens from the blood (entraps and destroys old erythrocytes)

red pulp

red or white pulp of spleen: upon exposure to the antigens, the lymphocytes of this pulp become sensitized to them and produce antibiotics to counteract them

white pulp

how does blood drain from the red pulp and empties into what?

blood drains from the sinuses of the red pulp to eventually empty into the splenic vein

the flow of lymph between lymph nodes and/or other lymphatic organs (spleen, tonsils, etc) relies largely on a combination of ______ muscular contraction and ___ ___ valves to prevent retrograde flow

skeletal; one-way

______ _______ are bean-shaped lymphatic organs connected by a vast network of lymphatic vessels

lymph nodes

what is the structure located within each lymph node that has an active center for B cells mitosis; also dendritic cells, phagocytic cells that make their way from the stratum spinosum of the epidermis, are closely associated with these structures?

lymph follicle

what captures antigens and brings them back to the lymph nodes?

dendritic cells

collections of lymphatic tissue associated with the inside of the throat, specifically located at the base of the tongue, back of mouth, and back of nasopharynx?

tonsils

what structure within the follicles of tonsils house proliferating B cells?

lighter stained germinal centers

which type of tonsil have several lymphoid nodules with numerous germinal centers?

palatine tonsils

the nodules of palatine tonsils are covered with what type of epithelium and invaginate at places into tonsillar crypts?

stratified squamous epithelium

initiates the development of immunocompetent T cells

thymus

does the thymus degenerates in adulthood?

yes

what is the diagnostic feature of the thymus and are sites that accumulate dead T cells, but are also involved in the development of regulatory T cells that help prevent autoimmune responses?

Hassall’s corpuscle

what is a cancer of the lymphatic system that if untreated and overgrows, can lead to the breakdown of both the splenic red and white pulp; chemotherapeutic advances have vastly improved the prognosis?

Hodgkin’s granuloma

what are characteristic of Hodgkin’s disease and are derived from B lymphocytes (considered crippled germinal center B cells), meaning they have NOT undergone hypermutation to express their antibody, they give the tissue a moth-eaten appearance?

Reed-Sternberg cells