During chordate evolution, what is the sequence (from earliest to most recent)in which the following structures arose?
1)amniotic egg
2)paired fins
3)jaws
4)swim bladder
5)four-chambered heart
A) 2, 3, 4, 1, 5
B) 3, 2, 4, 1, 5
C) 3, 2, 1, 4, 5
D) 2, 1, 4, 3, 5
E) 2, 4, 3, 1, 5

Question

Quizplus · Accepted Answer

The correct sequence reflecting the evolution of these structures in chordates starts with paired fins, which are a primitive feature found in early fish. Jaws came next, providing a significant evolutionary advantage in feeding. The swim bladder evolved as a buoyancy control organ, which is believed to have evolved from lungs. The amniotic egg allowed for the colonization of terrestrial environments by preventing desiccation of the embryo. Finally, the four-chambered heart is a more advanced feature that evolved to support the high metabolic demands of endothermy in birds and mammals.

During Chordate Evolution, What Is the Sequence (From Earliest to Most