Various branches used in biology include those pertaining to animals, evolution, the environment and chemistry. Branches covering microorganisms and microscopic structure are grouped together, as are subsections related to the medical field.
Biology groupings in the medical field include anatomy, endocrinology, psychology, surgery and toxicology. Branches about microscopic structure include cytology, histology and microbiology. Common divisions of biology that deal with animals are zoology, mammalogy, ichthyology and entomology, which is the study of insects. Different branches of biology that cover evolution include evolutionary biology and paleontology, while those covering the environment include ecology, limnology, cryobiology and conservation biology. Biochemistry and molecular biology relate to chemistry.