White Blood (WBC) – Leukocytes Flashcards
- 5,000-10,000
- Has nucleus
- no hemoglobin
- Less numerous and larger than RBC
- Most live in few days except lymphocyte can live for several months or years
- Combats pathogen by phagocytosis and immune response
- They will eat up the microorganism or through immune response
White Blood (WBC) – Leukocytes
➢ process by which WBC leaves the bloodstream by being able to deform, elongate, squeeze through pores of capillaries to reach injured tissue
Diapedesis
- Granular Leukocytes:
a. Neutrophils
b. Eosinophils
c. Basophils
➢ process by which neutrophil and other WBC are attached to the chemicals released by microorganisms at the site of infection or injury
Chemotaxis
Types Of White Blood Cell
- Granular Leukocytes
- Agranular Leukocytes
o Percentage: 60-70% (most numerous leukocyte)
o Structure: Nucleus with 3-5 lobes; Barr body (inactive X chromosome) visible in females, which aids in sex identification.
o Function:
➢ First line of defense, responding quickly to bacterial infections.
➢ Contains lysozyme to break down bacteria.
➢ Stains neutral (pink-blue).
➢ Elevated during acute bacterial infections; after fighting microorganisms, neutrophils and microorganisms die together, forming pus.
Neutrophils
o Percentage: 2-4%
o Structure: Nucleus with 2 lobes.
o Function:
➢ Granules contain lysozymes and peroxidases to destroy intruders.
➢ Stains pink in acidic dyes.
➢ Phagocytizes antigen-antibody complexes and destroys certain parasitic worms.
➢ Combats histamine effects in allergic reactions by releasing histaminase.
➢ Elevated during allergic reactions or parasitic infestations.
Eosinophils
o Percentage: 0.5-1% (least common granulocyte)
o Structure: Large, coarse granules that stain dark blue and obscure the S-shaped nucleus.
o Function:
➢ Releases heparin (anticoagulant) and slow-reacting substance of anaphylaxis (SRS-A), which is involved in severe allergic reactions.
Basophils
- Agranular Leukocytes
a. Lymphocytes
b. Monocytes
o Percentage: 20-25% (most numerous agranular leukocyte)
o Structure: Large nucleus with a thin ring of cytoplasm; lacks specific granules and is not phagocytic.
o Function:
➢ Produced in bone marrow and lymphoid tissues.
➢ Produces antibodies to fight infections.
➢ Elevated in cases of acute viral and chronic bacterial infections.
Lymphocytes
Types of Lymphocytes
▪ B-Cells
▪ T-Cells
▪ NK (Natural Killer) Cells
➢ Responsible for humoral immune response.
➢ Transforms into plasma cells to produce antibodies.
B-Cells
➢ Mediates cellular immune response by directly attacking microorganisms.
T-Cells
➢ Large granular lymphocytes; essential for the innate immune system.
➢ Provides rapid response (within 3 days) to virusinfected cells.
➢ Acts as a type of cytotoxic lymphocyte.
NK (Natural Killer) Cells
o Percentage: 3-8%Structure: Largest of the formed elements, with a kidney-shaped or horseshoe-shaped nucleus.
o Characteristics:
➢ Stays in the bloodstream for about 3 days before transforming into macrophages.
➢ Capable of phagocytosis, making it a crucial element in immune defense.
Monocytes
