blocking the activity of acetylcholinesterase a)would make the muscles less excitable. b)would produce muscle weakness. c)would cause spastic paralysis (muscles are contracted and unable to relax). d)would cause flaccid paralysis (muscles are relaxed and unable to contract). e)would have no effect on skeletal muscles.

the answer is :

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.