The pathogenesis of HIE in the newborn period involves the same key players that are also present in adults, namely energy crisis from hypoxia-ischemia, lactic acidosis, excitotoxicity, and free radicals, but there are some important modifiers, which account for different patterns of pathology in newborn babies.
Chordates (phylum Chordata) are a group of animals that includes all the vertebrates (subphylum Vertebrata), as well as two subphylum of invertebrates, the Urochordata (tunicates) and the Cephalochordata (lancelets).lso, the relationships of some chordate groups are not very well understood. 1  Phylum Chordata. 2  Subphylum Urochordata (Tunicates). 3  Subphylum Cephalochordata (Lancelets). 4  Class Myxini or Hyperotreti (hagfish). 5  Subphylum Vertebrata (Vertebrates-animals with backbones). 6  Class Conodonta (Conodonts).
Chordates are coelomate animals that possess: 1  a supporting rod or notochord; 2  a single hollow dorsal nerve cord; â 3 metameric segmentationâ: division of the body muscles into similar units, known as segments, that are arranged serially one behind the other;hey differ from the invertebrate chordates in possessing 1  : an internal skeleton, including a vertebral column which encloses the nerve cord; 2  a brain enclosed in a skull; 3  a pumping heart and efficient blood circulation.