Zoology is a branch of science which deals with the study of animals while Biology is a branch of science which deal with the study of all living things. Since animals are living things, we can say that zoology is under the field of biology.

In biology, there is what we so call as taxonomy which names living organisms based from their rank or level in the ecosystem like genus and specific epithet. Also, you could consider the main components of living things specifically their cells (cell and molecular biology), tissues (histology), organs, and organ systems as well as their anatomy, physiology, and morphology.