Histology is the branch of biology that uses a microscope to study the structure, formation and function of tissues, cells, extracellular components and organs.
Histology which is also known as microscopic anatomy (or microanatomy) is to be contrasted with gross anatomy. Gross anatomy involves structures that can be observed using the naked eye. Histology always uses a microscope.
The word anatomy derives from the Greek ‘ana’ which means ‘up’ or ‘through’, and ‘tome’ meaning ‘a cutting’. In the past, people learned the structure of a body by dissecting it or cutting it up. The word Histology derives from the Greek ‘histo’ meaning ‘tissue’ and ‘ology’ which means ‘knowledge’. Histology was the treatise or written explanation on the subject about the tissues of the body and its cells.
Histology is the foundation for pathology since accurate diagnosis of diseases requires histopathological examination of samples. The tissues of a body are examined using either autopsy, surgery or biopsy. They are then put through a process to be stabilized and to prevent decay. Once this is done and the tissues have been turned into a hard block, very thin sections of the tissues (5 – 7 micrometers, which is thinner than an average cell) can be sliced and placed on the glass slide for staining with one or more pigments. The reason the slice of tissue has to be stained is because it would otherwise be virtually transparent under the microscope. The science of tissue staining is called histochemistry.
Web Resources On Histology
Histology & Organ Systems
Book Resources On Histology
Basic Histology: Text and Atlas by Luiz Carlos Junqueira and Jose Carneiro
Human Histology by A Stevens and J Lowe