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).
There are four key characteristics to chordates. They are the  presence of a notochord, the presence of a hollow nerve cord that  is dorsal to the notochord, pharyngeal pouc â¦ hes and an endostyle.t some point in their lives, a chordate will have a notochord, a nerve cord that runs down their back, and a slit in the throat area. The phylum name Chordata came from the n â¦ otochord, a flexible rod that supports the back. They include fishes, amphibians, and reptiles.