This sub-field of biological study is the science of plants. Botanical studies include examining the development of plants, their life cycles, ecology, evolution and structure.
This branch of biology studies animals, including their development, physiology, structure and classification.
Anatomy focuses of the structure, shape and relationship between bodily parts of organisms. It includes the study of the human body, animals and plant structures.
Another sub-field of biology is physiology, which is the science that looks at the inner workings and functioning of living systems, such as the body's organs and respiratory system.
Embryology studies the formation and early development of organisms. Embryologists examine the embryo and its development from a single cell to the point is becomes a fetus.
Genetics deals with mechanisms of hereditary transmission. This biological sub-field examines the inheritance of characteristics and variations between related or similar organisms.
Evolution studies the origins of living species and the relationships among them. Evolutionary biology also looks at how species have changed over time by examining their descent.
This field involves the study of ecosystems and the relationships between plants and animals that occur within these environments. Studies may focus on the harmony of such interactions in land, air or water-based environments.
Taxonomy is the study of how organisms are named and classified. Classifications are based upon an organism's evolutionary origins with each grouped within a taxa. This sub-field offers a method of organizing the immense diversity of life on earth.
Some authors like James Kiura define botany and zoology as the main branches of biology, with all other fields stemming from these. In contrast, Biology Online identifies almost 50 sub-fields of biology on its branches of biology page (see References). Some of the other subfields identified by this online resource include bioengineering, pathology, marine biology, toxicology and virology.