Question
Fish have only two chambers in their heart, and blood passes through the heart only once per body cycle. This is because: heart first
Fish do not need oxygen
Blood goes to the gills for oxygenation and then directly to the body, without returning to the
Fish have no blood vessels
Fish have double circulation like mammals
Detailed Explanation
In fish, deoxygenated blood is pumped to the gills where it is oxygenated and then passes directly to the rest of the body, so it goes through the heart only once per cycle.