1. Which is a characteristic of chordates?all chordates have a backboneall chordates live on landall chordates have a notochordAll chordates breathe air

To answer the question, we need to analyze the characteristics of chordates and determine which statement is accurate.

Analysis of Options

1. All chordates have a backbone: This statement is partially true, as vertebrates (a subgroup of chordates) have a backbone, but not all chordates possess a backbone (e.g., tunicates and lancelets do not have a backbone).

2. All chordates live on land: This is incorrect. Chordates can be found in various habitats, including aquatic environments (e.g., fish) and terrestrial environments (e.g., mammals, birds).

3. All chordates have a notochord: This statement is true. One of the fundamental characteristics of chordates during at least some stage of their development is the presence of a notochord, which provides support.

4. All chordates breathe air: This statement is not correct as many chordates, such as fish, breathe water using gills rather than air.

Conclusion

Based on the above analysis, the most accurate characteristic of all chordates is:

All chordates have a notochord.