19.4 Formed elemenets (leukocytes) Flashcards
what is the fn of WBCs?
protect body against microorganisms and remove dead cells and debris
what type of movement do most WBCs exhibit?
ameboid
describe ameboid movement
the ability to move like an ameba, by putting out irregular cytoplasmic projections
what is diapedesis?
the WBCs become thin and elongated and move either between or through the endothelial cells of the capillary walls
when does a WBC use diapedesis?
when it leaves the circulation to enter tissues
what is the attraction to and movement toward foreign materials or damaged cells called?
chemotaxis
what is pus?
the accumulation of dead WBCs and bacteria
what is the most common type of WBC?
neutrophil
what type of WBC is a neutrophil?
granulocyte
what name is given to a neutrophil to describe its nuclei that are multilobed and can occur in more than one form?
polymorphonuclear neutrophil or PMN
how long does a neutrophil remain in circulation?
10-12 hours
what type of materials are usually phagocytized by neutrophils?
bacteria, antigen-antibody complexes, other foreign matter
what type of cell is most likely to phgocytize bacteria, antigen-antibody complexes, other foreign matter
WBC, neutrophil
what is a lysozyme?
an enzyme from a lysosome to destroy bacteria
what type of cell is most likely to secrete lysozymes?
WBC, neutrophil
how long do neutrophils survive after they leave the circulation?
1-2 days
what type of WBC is an eosinophil?
granulocyte
how does an eisinophil respond to inflammation?
leaves circulation
minimize inflammation by secreting a chemical that destroys histamines
what is the fn of an eisinophil?
minimize inflammation
use toxic chemicals to attack parasitic infections
what type of parasites are eisinophils likely to attack?
hookworms, tapeworms, flatworms
what type of WBC is the least common?
Basophil
what type of WBC is the most common?
neutrophil
what type of WBC is a basophil?
granulocyte
what WBCs are granulocytes?
neutrophils
eosinophils
basophils
what WBCs are agranulocytes?
lymphocytes
monocytes
how do basophils respond to inflammation?
promote it by releasing histamines
what 2 chemicals do basophils release?
histamines and heparin
what cell releases both histamines and heparin?
basophil
which is the smallest WBC?
lymphocyte
what type of WBC is a lymphocyte?
agranulocyte
which WBC is only slightly larger than its nucleus?
lymphocyte
where is a lymphocyte produced and what is its target tissue?
produced in marrow, travels through blood to lymph tissue
what type of cell is produced in the marrow and travels to lymph tissue?
lymphocyte
what are the 2 places of production of lymphocytes?
initial production in marrow
division and production in lymph tissues
what are the lymph tissues that contain lymphocytes?
lymph nodes, spleen, tonsils, thymus
what are 2 specific types of lymphocytes?
B cells
T cells
what is the fn of B cells?
to produce antibodies
what stimulates B-cells to produce antibodies?
bacteria
toxins
what is the fn of T-cells?
protection against viruses, tumor cells, responsible for graft rejection
what type of cell is a target for T-cells?
any rapidly dividing cell
what type of WBC is a monocyte?
agranulocyte
which is the largest WBC?
monocyte
how long is a monocyte usually in the circulation?
3 days
what does the monocyte become outside of the circulation?
macrophage
what is the fn of monocytes?
phagocytize debris, bacteria, viruses dead cell and cell fragments as a macrophage
