In class, we discussed an experiment in which 2 hearts were placed in different beakers of saline solution. Heart # 1 had the vagus nerve connected, while heart #2 did not. The beakers were connected by a tube that allowed saline to diffuse from one beaker to the other. Stimulation of the vagus nerve connected to the first heart slowed the contraction rate of heart #1.Atropine, a drug purified from the nightshade plant, is an antagonist for muscarinic acetylcholine receptors. In the experiment with 2 hearts, what would have happened if atropine was put into the saline solution, then the vagus nerve was stimulated?
A) contraction rate of heart #1 would increase, but contraction of heart #2 would not change
B) contraction rate of heart #1 would decrease, but contraction of heart #2 would not change
C) contraction of both hearts would increase
D) contraction of both hearts would decrease
E) contraction rates of both hearts would NOT change
