Because there is genetic variation among the newly reproduced organism.
An organism that exhibits a head with sensory equipment and a brain probably also have receptors, which capture the stimuli of the environment and transform them into a nervous impulse, and organs of the senses that are the communication channels we have with the environment and thanks to them we understand and interpret the environment, they are: vision, hearing, smell, taste, and touch.
Well, it's obvious, because without a transport system, cells wouldn't have the nutrients and things they needed!! And waste wouldn't be able to circulate out of cells.
