Chapter 21 The Lymphatic System

Basophils
• secrete chemicals that aid mobility and action of
WBC other leukocytes
– leukotrienes – activate and attract neutrophils and
eosinophils
– histamine – a vasodilator which increases blood flow
• speeds delivery of leukocytes to the area
– heparin – inhibits the formation of clots
• would impede leukocyte mobility
• mast cells also secrete these substances
– type of connective tissue cell very similar to basophils
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