Anatomy is the identification and description of the structures of living things. Anatomy is a branch of biology and medicine which can be divided into three broad areas: human anatomy, zootomy (animal anatomy), and phytotomy (plant anatomy).
The word anatomy comes from the Greek ana- meaning “up”, and tome- meaning “a cutting”. Anatomy, especially in the past, has depended heavily on dissection. In Greek and Latin the words “anatomy” and “dissection” have virtually the same meanings. Although both words have similar origins, anatomy has evolved to become a broad discipline of its own, while dissection remains a technique of anatomical science.
Anatomy can be divided into Gross Anatomy (macroscopic anatomy) and Microscopic Anatomy.
What is Gross Anatomy?
In medicine, gross anatomy, also known as topographical anatomy or macro anatomy, refers to the study of the biological structures that may be seen with the naked eye.
Gross anatomy may involve dissection or noninvasive methods; the aim is to acquire data about the larger structures of organs and organ systems.
In dissection, the human or animal cadaver is cut open and its organs are studied. Endoscopy, inserting a tube with a camera at the end, might be used to study structures within living animals. There are non-invasive way of studying, for example, the blood vessels of living animals or humans; an opaque dye may be inserted into the animal to observe the circulatory system (angiography). Live beings may also be studied using MRI (magnetic resonance imaging) or X-ray.
Medical and dental students, as part of their course, will have to perform some kind of practical work in gross human anatomy, this will involve dissection. In many cases, the students dissect human corpses (cadavers).
What is Microscopic Anatomy (Histology)?
Microscopic anatomy, also known as histology, is the study of cells and tissues of animals, humans and plants that are too small to been seen with the naked eye. Microscopic anatomy commonly involves studying tissues and cells by sectioning and staining (histological techniques), and then looking at them under an electron or light microscope.
Sectioning – is cutting tissue into very thin slices so they can be examined. Histological stains are added to biological structures (such as tissues) to add colors or to enhance their colors so they can be more easily distinguished when they are examined, especially if different structures are next to each other. Histology is a discipline that is vital for the understanding and advancement of medicine, veterinary medicine, biology, and some other sub-disciplines of the life sciences.
Histology is used for:
Teaching – histology slides are commonly used in teaching labs to help students who are studying the microstructures of biological tissues.
Diagnosis – tissue samples (biopsies) are taken from patients and sent to the lab for analysis. The people in those labs are histologists.
Forensic investigations – the microscopic study of biological tissues can help explain why, for example, somebody unexpectedly died.
Autopsies – as in forensic investigations, biological tissues from deceased people (and animals) can be analyzed, so that investigators may better understand the causes of death.
Archeology – biological samples from archeological sites can provide useful data about what was going on in history or ancient history.