Circulatory System 10

This is another section of heart, showing both "standard" cardiac muscle and a band of Purkinje fibers (upper portion of the field). Why are the Purkinje fibers so pale? Where are they found, and what is their function? Note the small vessels at the *s; these are examples of vasa vasorum.

Slide K-10, field S19 of finder slide A, 6.3X objective.