Electric Polarity in the Chorioallantoic Membrane of the Chick Embryo. ∗

Abstract

Conclusions

The experiments discussed here indicate that a potential difference, requiring the expenditure of metabolic energy, is maintained across the chorioallantoic membrane, the inner surface being negative. Its value is somewhat smaller than the potential observed across most other biologically active membranes (1), and it is unlikely that these small electric forces would act directly as organizing agents in a tissue graft on the membrane. Nevertheless the potential difference may be an expression of an underlying metabolic asymmetry, maintained for example by a gradient of CO₂ or O₂ across the membrane, which could be related more relevantly to the observed polar reconstitution of the organs in the experiments of Weiss and Taylor.