Are Fish Unidirectional Breathing Or Bidirectional?
Are Fish Unidirectional Breathing Or Bidirectional? (a) Fish have the simplest circulatory systems of the vertebrates: blood flows unidirectionally from the two-chambered heart through the gills and then the rest of the body. What is unidirectional flow in fish? With unidirectional flow, there is no mixing. Another factor is the countercurrent movement of blood and