We should expect that the rat will have have more difficulty in learning the task compared to a normal rat. This is because the rat has been injected with a certain drug that oppresses the dopamine activity. And then the rat is placed in an operant chamber where a lever-pressing task is shaped through positive reinforcement.
Subsets of {dog, cat, fish} are Ф, {dog}, {cat}, {fish}, {dog, cat}, {dog, fish}, {cat, fish}, {dog, cat, fish}.
Enzymes are in the Proteins class
