Question: 170: Which of the following animals has three chambered heart?
(1) Scoliodon
(2) Hippocampus
(3) Chelone
(4) Pteropus
Answer: Option (3)
Explanation:
The number of chambers in the heart varies among different groups of animals.
Scoliodon (dogfish) and Hippocampus (seahorse) are fishes,
and fishes possess a two-chambered heart consisting of one atrium and one ventricle.
Chelone is a turtle, which belongs to class Reptilia.
Most reptiles have a three-chambered heart consisting of two atria
and one incompletely divided ventricle.
Pteropus (bat) is a mammal, and all mammals have a four-chambered heart with two atria and two ventricles.
Therefore, the animal with a three-chambered heart is Chelone.