THE LYMPHOID SYSTEM IMMUNITY Flashcards
(88 cards)
ability of an individual to resist infections by means of normally present body functions
natural immunity
The most important process of internal defense mechanism is the process of
phagocytosis
how many percents do lymphocytes constitute in the circulating wbc’s ?
20-40%
The second dominant type of WBC after Neutrophils
lymphocytes
Cytoplasm is SPARSE, containing few organelles and NO SPECIFIC GRANULES, and consists of a narrow ring surrounding the nucleus.
lymphocytes
These cells are unique, because they arise from a __ and then are further differentiated in the primary lymphoid organs.
hematopoietic stem cell
__organs is where the maturation of B and T cells occurs
Primary lymphoid
mother of all cells , origin of all cells in the body
Hematopoietic stem cells
hematopoietic stem cells can be differentiated into two, what are they?
common lymphoid precursor and common myeloid precursor
Lymphocyte circulation is complex and is regulated by different cell surface adhesion molecules and by chemical messengers called ___
cytokines
where does the t cell differentiation occurs?
thymus
b cell differentiattion occurs in
bone marrow
- Once the cell matured, they travel to the ___ for proliferation and differentiation
secondary lymphoid organs
what are the 3 major population of lymphocytes
t cell, b cell, and nk cell
give the percentage of each major population of the lymphocytes
- 61-80% - T cells,
- 20 % - B cells,
- 10-15% - NK cells
whata re the 2 primary lymphoid organs?
bone marrow and thymus
whata re the example of secondary lymphoid organs
- Spleen,
- Lymph nodes
- Mucosal-Associated Lymphoid Tissue (MALT)
- Appendix
- Tonsils
- Peyer’s Patches
- Cutaneous-Associated Lymphoid Tissue (CALT
which precursor do - T cells, B cells, and NK cells arise from
common precursor known as the CLP or common lymphoid precursor cell
o ___ fills the core of all flat long bones and is the main source of hematopoietic stem cells, which develop into different cell types.
Bone marrow
it is the source of our hematopoietic stem cell
bone marrow
is an organ which is small, flat, bilobed organ found in the thorax, or chest cavity, right below the thyroid gland and overlying the heart.
thymus
T cells developed their identifying characteristics in
Thymus
weight of thymus at birth, puberty, and old age
- 30 g (at birth) →35 g (puberty) →atrophy
- Each lobe of the thymus is divided into ___ filled with epithelial cells that play a central role in this differentiation process.
lobules