Parental permission should be waived for research in gsd youth when:

The correct answer to this open question is the following.

Parental permission should be waived for research in GSD youth when research protocol is designed to examine conditions in children when familial approval is not a sound condition to protect the subjects. Under some cases, an Institutional Review Board may waive the terms for obtaining parental consent.

the reason the two sea urchins don't compete with each other for food, resources, etc. is because the urchins have adapted to the environment but they have also adapted to each other. this is most likely because the genes of the sea urchins.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.