Chorion permeability

There is evidence that the chorion may reduce exposure of zebrafish embryos to some compounds (31), and the environmental conditions in which embryos are grown may affect chorion permeability (32). However, the degree to which the chorion serves as a barrier to chemical exposure is controversial and poorly understood. Some have concluded that the effects are too small to justify the efforts of dechorionation (5). Dechorionation removes the possibility of decreased exposure to chemicals in the embryo medium, but damage to the embryos can sometimes result. It is, therefore, important to ensure that removal is done with as much care as possible. 

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