Are most mutations harmful, helpful, or neutral!?

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

Penelope studies how the structure and function of the nervous system is related to behavior. she is a psychologist

Explain the physiological changes that occur when the hypothalamus stimulates the sympathetic nervous system. you can make a flowchart or a simple step process. be sure to include all chemicals/hormones secreted, glands involved and the functions of each chemical/hormone.