An important characteristic that Hemichordates share with Chordates is:
| 1. | Ventral tubular nerve cord |
| 2. | Pharynx with gill slits |
| 3. | Pharynx without gill slits |
| 4. | Absence of notochord |
Choose the correct statement.
| 1. | All mammals are viviparous |
| 2. | All cyclostomes do not possess jaws and paired fins |
| 3. | All reptiles have a three-chambered heart |
| 4. | All Pisces have gills covered by an operculum |