Beginning with depolarization at the neuromuscular junction, describe the normal sequence of events which lead to muscle contraction

Depolarizing urges release Ach from the nerve ending, which diffuses across the neuromuscular junction. At the muscle membrane, Ach attaches to receptor sites. As sodium channels begin to open, ions cross the membrane. Also, the action potentials are then elicited. 

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation: