Chordata Phylum
The Chordata Phylum include mammals, fish, amphibians, reptiles, and birds. Much like the crustaceans, who are apart of the anthropada phylum, the fish share the same respiratory system as they both require gills to breathe. Some amphibians have normal lungs, but they have a slow diffusion rate for the oxygen to enter the bloodstream. Most amphibians have the ability to gain oxygen only through their skin. The rest of the organisms under chordata have normal lungs that operate similarly to human lungs.
Eagle
Like most mammals, the eagle has lungs that allow it to breathe oxygen. The eagle is capable of breathing through their nasal passages. The oxygen travels through into the lungs, which will supply oxygen for cells to perform their tasks. They also release carbon dioxide the same way.
Cobra
Much like the eagle, the cobra can breathe through their nasal passage. The oxygen will then be sent down to their lungs, thus supplying oxygen to the cells. Due to the cobra's size, the lungs are bigger, allowing them to hold their breath longer because they could get more oxygen. However, because the cobra is cold-blooded, they do not require as much oxygen as other organisms do.
Crocodile
The crocodile is a water based organism, but does not contain any gills that allow it to breathe underwater. The crocodile will raise its head out of the water to take in the oxygen. Much like the other examples, the crocodile will breathe through their nasal passages and bring the oxygen into the lungs. They will also release carbon dioxide the same way.