Differences Between Histology and Cytology

Histology vs Cytology

Every organism on earth is made up of either a cell or collection of cells except viruses. Cell is defined as the smallest structural and functioning unit of an organism. A group of cells that performs a common function and has a similar origin is called a tissue. Organs are composed of various tissues to do the functions efficiently. A collection of organs is known as an organ system. The animal or plant body can be formed of different levels of organization, with increasing complexity of each level from cell to organ system. Hence, unicellular organisms have simplest structure while the most multicellular organisms have very complex structures.


Histology is the study of the structure and function of microscopic anatomy of plants and animals. Microscopic anatomy includes the cells, tissues, organs and organ system of an organism. These studies are performed especially by examining cells and tissues.

First particular part of an organ is selected. Then staining is done followed by an examination under a light or electron microscope. Microscopes are the basic tools used in the histological studies. Histological stains are very important as they enhance the ability of visualizing and differentiating of microscopic structures.


Study of structure, function and chemistry of cells is known as cytology. It is a branch of biology which deals directly with the structural and functional organization of cells and also with the other phenomena such as metabolism, ontogenetic differentiation, heredity, and phylogeny.

Cytology vs Histology

• In cytology, we go only for cellular level, but in histology, we mainly examine the tissue architecture of a particular tissue.

• The study of cellular structure and function is called cytology, while the study of cells and tissues in an organism is called histology.

• The costs for histological studies are higher than cytology.

• In cytology, it mainly aims the cells. Therefore, the cytological observations have excellent cellular details unlike in the histological observations.

• Tissue details are present only in histology while details of tissue architecture cannot be observed in cytology.