Animal anatomy and physiology is the study of the various different components which animals are composed of and how these different structures work together to allow animals to function. The animal kingdom, Animalia, is comprised of a number of different classes, both invertebrates and vertebrates, which all vary in terms of complexity.
Invertebrates are simpler organisms in comparison to vertebrates. A major difference between invertebrates and vertebrates has to do with their skeleton or lack thereof. Invertebrates are species which do not have a backbone, whereas vertebrates do have an internal skeleton. In addition to this major difference, there are other anatomical differences between these two animal categories.
All species which are part of the animal kingdom fall under the phylum Chordata. Chordates all possess a set of particular features which are present at some stage in an animal’s life. For example, in humans most of these features are present during the embryonic stage. These features include pharyngeal slits and a notochord, among a few others.
Invertebrates and vertebrates both contain a multitude of different classes, with each of these classes maintaining species which are most similar with each other. The study of animal anatomy and physiology investigates the structures which are similar among each class and the specific ways in which all the species within each class function. As species move from invertebrates to vertebrates their modes of locomotion, their respiratory organs and their mechanisms for reproduction among other things, change and generally become more complex.
Animal anatomy and physiology is an integral field of biology and in order to truly understand animal biology, examining the specific features unique to all species is important. However, despite the major differences between all organisms, some similarities do exist. Uncovering these characteristics is one of the main objectives of animal anatomy and physiology.