Question

Why ethanol decreases the heart rate. How would the addition of ethanol affect the homeostasis in Daphnia and human?

Answer 1

Ethanol decreased the heart rate due to a decrease in action potentials. The reason for decreased action potentials in daphnia due to ethanol consumption is unknown, as it could be decreased acetylcholine release, lowered sensitivity of acetylcholine receptors, or a combination of both.

In one of the studies, it was concluded that ethanol alcohol caused the heart rate of the daphnia to decrease, in this case, due to a decrease in action potentials in the organism due to the decrease in action potential which is due to the postsynaptic receptors being much less sensitive. Daphnia has a myogenic heart like us i.e their hearts beat due to spontaneous heart muscle activity rather than in response to the pacemaker activity of the cardiac ganglion.