Question

A) What is the function of the white pulp in the spleen? What is the function of the red pulp?

What is the function of the cortex of the thymus? What is the function of the medulla of the thymus?

B) Are there lymph vessels in the epidermis? Why or why not?

   Are there lymph vessels in the brain? Why or why not?

   Are there lymph vessels in the cartilage? Why or why not?

   Are there lymph vessels in the bone? Why or why not?

Answer 1

A)

RED PULP

Area containig large number of RBC

Structurally consist of networ of reticular fibers rich in macrophage

composed of splenic cord and splenic sinusoid

mainly concerned with disposal of Dead RBC and blood born pathogen

WHITE PULP

Area resembling lymphoid nodules

composed of composed of lymphocyte trapped in  reticular fibers

main function is immunity by Tlymphocyte,B lymphocyte and Macrophages

2)CORTEX OF THYMUS

thymic cortex contain developing T-lymphocytes. Mitotic figures are seen in the cortex. They  are dividing lymphoblasts in the process of producing clones of smaller mature T-cells.

The epithelial cells in the cortex of the thymus express class I and class II MHC and serve to positively select immature T-cells.

in the corticomedullary junction,macrophages remove lymphocytes that have undergone death because they failed to develop properly

Thymus medulla

The medulla of the thymus contains T-lymphocytes and more numbers of epithelial cells .

The epithelial cells present in the medulla of thymus provide structural support to the medulla and negatively select self-reactive T-cells to generate resistance against self-antigens.

A distinguishing identity  of the medulla is the presence of Hassall’s corpuscles which are concentric arrangements of flattened epithelioid cells that are acidophilic.

B)

Epidermis doesno have lymphatic vessels because epidermis lack blod vessels.They are avascular structure

Brain doesnot have lymphatic blood vessels .The function of the Lymphatic syste are done by CSF

Cartilage are avascular structure which lack lymphatic vessels

periosteum of teh bone contain lymphatic vessel but the bone marrow doesnot have lymphatic vessels