question_answer 54)

    In which of the following vertebrate group/groups, heart does not pump oxygenated blood to different parts of the body? (a) Pisces and amphibians                                            (b) Amphibians and reptiles (c) Amphibians only                                                        (d) Pisces only

Answer:

                  (d) In Pisces (fishes), the heart is 2 chambered oral pumps deoxygenated blood to me gills, where oxygenation takes place by diffusion. The oxygenated blood from the gills is supplied to the body parts where oxygen is utilized and CO2 enters H making the blood deoxygenated. This deoxygenated blood returns to the heart. Thus, it has single circulation, i.e., blood passes through the heart only once during one complete cycle.