Given a scientific question, generate a correct answer to it.

[Q]: Vertebrates. from the smallest of fish to us. one of the main features we all have in common is our what?
[A]: backbone

[Q]: What is the name of a microorganism that is considered important for living resources in all ecosystem?
[A]: bacteria

[Q]: Robert merrifield developed the first synthetic approach for making what essential cell substances in the lab?
[A]:
proteins