Which of the following classes of animals has/have three-chambered

Which of the following classes of animals has/have three-chambered heart?

[amp_mcq option1=”Pisces and Amphibia” option2=”Amphibia and Reptilia” option3=”Reptilia only” option4=”Amphibia only” correct=”option2″]

This question was previously asked in
UPSC CDS-1 – 2018
The correct answer is B) Amphibia and Reptilia.
Amphibians (like frogs, salamanders) typically have a three-chambered heart consisting of two atria and one ventricle. Most reptiles (like lizards, snakes, turtles) also possess a three-chambered heart with two atria and a single ventricle, although the ventricle is often partially divided by a septum, reducing mixing of oxygenated and deoxygenated blood. Crocodiles are an exception among reptiles, having a four-chambered heart.
Fishes (Pisces) have a two-chambered heart. Birds and Mammals both have a four-chambered heart. The evolution from two to three to four-chambered hearts reflects increasing efficiency in separating oxygenated and deoxygenated blood, which is beneficial for higher metabolic rates in endothermic animals (birds and mammals).
Exit mobile version