What are crab and lobster carapaces composed of?

Ineed asap with this question as well organisms evolve, through the process of natural selection, in ways that enable them to live successfully in their environments. choose three biomes or aquatic ecosystems and describe how abiotic factors have influenced the organisms that live there

5) these are organisms where the genetic material is not bound by a nucleus. they are usually unicellular.

Cells are adapted to preform specific functions. which of the following terms refers to this capability?