Lymphatic System III Flashcards
- A blind sac stemming from the wall of the first part of the large intestine.
- Its walls contain a large concentration of lymphoid follicles.
- Can also be overwhelmed by bacteria.
Appendix
If the mouth of the appendix becomes plugged, the pressure inside rises.
Appendicitis
A ruptured appendix can be life-threatening because it spills ____ into the otherwise sterile peritoneal cavity.
Pathogens
- Found in the mucosa of the distal portion of the small intestine.
- Made up of many lymphoid follicles in the small intestine.
- Located where they can sample the antigens moving through hollow organs open to the external environment.
Peyer’s Patches
- Primary lymphoid organ.
- Site for differentiation of lymphocytes into mature T cells.
- Located in the mediastinum.
- Is at its greatest size and activity in young children.
Thymus
____ influence the development of immature T cells.
Thymic Hormones and Other Factors
As we age, the thymus decreases in size and activity as the thymic tissue is gradually replaced by fat and connective tissue.
Thymic Atrophy
Divided into lobules, which contain an outer cortex and an inner medulla.
Thymic Lobes
Most cells in the thymus are ____ at various stages of development.
Immature T Cells
Cells that influence T cell development and secrete thymic hormones.
Thymic Epithelial Cells
- Distinctively shaped structures within the medulla.
- Clusters of keratinized epithelial cells with a whorled appearance that are scattered throughout the medullary area.
- May be involved in the development of a type of T cell called a regulatory T cell.
Thymic Corpuscles
Consists of immune cells and lymphoid organs and tissues.
Immune System
Two types of phagoyctes.
Neutrophils and Macrophages
Three types of antigen-presenting cells.
- Dendritic Cells
- Macrophages
- B Cells
Primary lymphoid organs where lymphocytes mature.
Bone Marrow and Thymus
