What branch of biology is concerned with the structure and function of plant and animal cells?

Cytology is the branch of biology that specifically studies the structure and function of cells, including both plant and animal cells. This field encompasses the examination of the various components of cells, such as the cell membrane, nucleus, organelles, and cytoplasm, and how these components interact and contribute to the overall life processes of the organisms. Cytology plays a crucial role in understanding cellular functions, development, and pathology.

In contrast, histology refers to the study of the microscopic structure of tissues, while pathophysiology focuses on the functional changes in the body resulting from disease processes. Microbiology, on the other hand, deals with microorganisms and their effects on other living organisms and the environment. Each of these fields has its own specific focus, making cytology the most relevant for the study of individual cells and their characteristics.