Page 211 - Atlas of Histology with Functional Correlations

FIGURE 6.9 ■ Basophil. Stain: Wright stain. Oil immersion.

FUNCTIONAL CORRELATIONS 6.3 ■

Leukocytes

Neutrophils have a short life span. They circulate in blood for some hours
and then enter the connective tissue, where they can survive for another a
couple of days. Although the cytoplasm of neutrophils appears neutral with

normal blood stains, electron microscopy images show that neutrophils
contain granules that are responsible for the cells’ functions. The two main
granules in the neutrophils are the larger azurophilic primary granules and

the smaller specific secondary granules. The primary granules are the
lysosomes that contain different lysosomal enzymes. The secondary granules
exhibit diverse functions, including productions of various enzymes and
enabling antibacterial functions of the neutrophils. Neutrophils are very
active phagocytes that concentrate at the sites of infection. They are attracted

by chemotactic factors (chemicals) produced by damaged or dead cells,
tissues, or microorganisms, especially bacteria, which they first surround,
phagocytose (ingest), fuse the phagocytized material with cytoplasmic

(primary) granules, and quickly destroy the organism with their potent
lysosomal enzymes.

Eosinophils also have a short life span and remain in blood for a period

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