 |
| Phylum Chordata |
|
| |
 Presence of a solid supporting structure on the dorsal side of the body called notochord. |
| |
 Presence of a dorsal hollow, tubular nerve cords. |
| |
 Presence of pharyngeal gill slits at least in the embryonic stages. |
| |
| The phylum is divided into 4 sub phyla. |
| |
| Hemichordata, Urochordata, Cephalochordata (together called as Protochordates) and Vertebrata. |
| |
|
 |
| |
 |
| |
| fig. 10.22 - Classification of Vertebrata |
| |
| The phylum is divided into six classes. |
| |
 |
| |
 |
| |
| fig. 10.23 - Examples of Pisces |
| |
 |
| |
| fig. 10.24 - Examples of Amphibians |
| |
 |
| |
| fig. 10.25 - Examples of Reptilia |
| |
 |
| |
| fig. 10.26 - Examples of Aves |
| |
 |
| |
| fig. 10.27 - Examples of Mammalia |
| |
|
| Mammals exhibit the following unique features also. |
| |
 Presence of mammary glands to nourish the young ones. |
| |
 Presence of muscular diaphragm that separates thorax from abdomen. |
| |
 Presence of external ear called pinna. |
| |
 Presence of seven vertebrae in the neck region. |
| |
 |
| |
| fig. 10.28 - Fish Anatomy |
| |
| |
