312 Chapter 13
Blood cell^ Life spanin blood^ Function^Erythrocyte 120 days O^2 and CO^2 transport^Neutrophil 7 – 12 hours Phagocytosis (^)
Eosinophil Unknown Defense against allergens (^)
and worms (^)
Basophil Unknown Inflammatory response (^)
Immune surveillance (^)
Monocyte 3 days (precursor of (^)
tissue macrophage)^
phagocytosis (^)
Antibody production (^)
B Lymphocyte Unknown (precursor of (^)
plasma cells) (^)
T Lymphocyte Unknown Cellular immune response (^)
®^
Platelets 7 – 8 days Blood clotting
Learning^
Cengage^
©^
Figure 13- 4 The life span and functions of blood cells.
In the second stage, prothrombin (proh-THROM-
bin), a plasma protein produced by the liver, is con-verted
into thrombin. In the presence of the calcium ions,
prothrombin activator converts the prothrombin into
thrombin.
In the third stage, another plasma protein, soluble
fibrinogen,- is converted into insoluble fibrin. It is the
thrombin that catalyzes the reaction that fragments
fibrinogen- into fibrin. Fibrin forms long threads that act
like a fish net at the site of injury. The fibrin forms what