Botany and zoology are further divided into various branches, each of which can be subdivided into areas of special study. Most major branches of the life sciences apply equally to plants and animals. Many of the branches, such as anatomy and physiology, overlap with, and contribute greatly to, the study of medicine. Anatomy Anatomy examines the structure of living things. Anatomists investigate the parts of organisms and how the parts are related.
Histology deals with tissues, and cytology with the fine structures of individual cells.
Comparative anatomy studies similarities and differences in the body structure of animals and provides clues to how certain animals might have evolved. Physiology Physiology deals with the normal functions of living things and their parts. For example, physiologists study how nerve fibers transmit impulses and how organisms take in and use food. Biochemistry examines the chemical processes that are involved in the actions of the different parts of plants and animals. Biophysics investigates the physical processes involved in the functioning of the various parts of living things.