Question

20. There has been an increase in the number of chambers in heart during the evolution of vertebrates.​

Answer 1

Answer:

The class of vertebrates are as follows;

1. Two chambered heart - Pisces, Example Promphet.

2. Three chambered heart - Amphibians, Reptiles - Example, Frog, Snake etc

3. Four chambered heart - Aves, Mammalia - Example, Birds, Humans etc

Answer 2

Answer:

Hey mate here is your answer....

Explanation:

▶️ Two chambered heart - Class chondrichthyes, Osteichthyes

▶️ Three chambered heart - Class Amphibia, Reptilia

▶️ Four chambered heart - Class Aves, Mammalia

Hope it helps!!☺️