If the versions of a gene for a trait are different, the organism is said to be Answer these pls!

Which system revise and send electrical signals throughout the body

Other than earth, is also known to have magnetic pole reversal? a: venus b: mars c: earths moon d: the sun

Which statement describes characteristics of planarians? a they live in oceans, are parasites, and reproduce only sexually. b they live in fresh water, are parasites, and reproduce only asexually. c they live in oceans, are free living, and reproduce sexually and asexually. d they live in fresh water, are free living, and reproduce sexually and asexually.