The size of an organism is most likely determined by a) its genes but not its environment b) its environment but not its genes c) its genes and its environment d) neither its genes or its environment

the peripheral nervous system or pns contains the nerves, which leave the brain and the spinal cord and travel to certain areas of the body. the peripheral nervous system's main job is to send information gathered by the body's sensory receptors to the cns as quickly as possible.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".