The effect of dispersion and aggregation
of melanin granules on the availability of the
substrate tyrosine and the enzyme tyrosinase.
Tyrosinase is attached to the pigment granules.
When the cytoplasm is in a sol state, substrate
can readily combine with exposed tyrosinase.
However, when the cytoplasm is in the gel state,
substrate cannot diffuse easily to reach the relatively
shielded tyrosinase