Robert is a 22-year-old who ate some of his aunt sophie's canned tomatoes for dinner last night. this morning, his speech is slurred and he is having trouble standing or walking, so his brother rushes him to emergency room. the doctor tells robert that he probably has botulism, a type of food poisoning. the toxin produced by this bacterium prevents the release of acetylcholine at the neuromuscular junction. explain how robert's symptoms are related to the effects of the toxin.