acids in biomass production and are reflected in the P content of the consumer. During early growth stages, or earlier instars, invertebrates may have higher demands for N and P enriched resources to fuel the ribosomal production of proteins and RNA. At later stages, the demand for particular elements may shift as they are no longer actively growing as rapidly or generating protein rich biomass. Growth rates of invertebrate organisms can also be limited by the resources that are available to them. See also Energy flow (ecology) Energy homeostasis References Ecology Stoichiometry