Question

During chordate evolution, what is the evolutionary sequence of the following structures, from earliest to most recent?

amniotic egg
four limbs with digits
jaws
lungs
four-chambered heart
Group of answer choices

A. 2, 3, 4, 1, 5

B. 3, 4, 2, 1, 5

C. 3, 2, 1, 4, 5

D. 2, 1, 4, 3, 5

E. 2, 4, 3, 1, 5

Answer 1

The evolutionary sequence of chordates from earliest to most recent is: lancelets, sharks, amphibians, snakes, and ostriches. Each step represents major developments like the backbone, cranium, and amniotic eggs, illustrating the evolution within the phylum Chordata.

Step-by-step explanation:

The evolutionary sequence of structures in chordates from earliest to most recent is as follows:

1. Lancelets
2. Sharks
3. Amphibians
4. Snakes
5. Ostriches (representing birds)

This sequence is based on the evolutionary history of vertebrates which are part of the phylum Chordata. The lancelets, as invertebrates, branched off first, possessing the distinctive features of chordates. Sharks, being jawless fish, represent an early form of vertebrates. Amphibians mark the emergence of quadrupeds. The evolution of snakes indicates the diversification of reptiles, while birds, such as ostriches, evolved later. Each step represents a significant evolutionary development such as the formation of the backbone, cranium, and amniotic eggs.