You roll a ball down a hill. The ball rolls for a distance and eventually comes to a stop. What stops the ball?

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.