Question

Single circulation i.e., blood flows through the heart only once during one cycle of passage through the body, is exhibited by 

(a) Labeo, Chameleon, Salamander 

(b) Hippocampus, Exocoetus, Anabas 

(c) Hyla, Rana, Draco 

(d) Whale, Dolphin, Turtle

Answer 1

The answer is (b) Hippocampus, Exocoetus, Anabas

In Option a) Chameleon is a reptile and Salamander is an amphibian which are having 3 chambered hearts and show partial double circulation. 

In Option c) all are Amphibians and they show partial double circulation. 

In option d) Whale is a mammal but turtle is a reptile hence option d) is wrong.