The cell membrane gateway system you are looking for is called <span>Sodium Potassium Pump.</span>
For #4) The correct answer is <span>A. because... Information in the DNA of the nucleus can tell muscle cells how to develop and perform special functions. </span>
Natural selection is where positive traits survive more, allowing those to become more common. Mutation is where radioactivity changes genes in a random way. Natural selection allows positive mutation to become more common. Adaptation is where natural selection works for a species specifically more a new habitat.