What causes variations in traits like hair color, eye color, and height

Which description best defines the nervous system and its two main branches? a: the message center of the body, split into the autonomic nervous system and the somatic nervous system b: the control panel of the body, split into the central nervous system and the exterior nervous system c: the message center of the body, split into the central nervous system and the peripheral nervous system d: the control panel of the body, split into the brain and the spinal cord

Which type of nerve creates a 'mental map" of the relative positioning of the body at any given point in time?

Abraham maslow's theory of personality development was the "ages and stages" model