In medicine, gross anatomy, macro anatomy, or topographical anatomy refers to the study of the biological structures that are visible to the naked eye.
The study of gross anatomy may involve dissection or noninvasive methods. The aim is to collect data about the larger structures of organs and organ systems.
In dissection, the scientist cuts open the human or animal cadaver is cut open and examines its organs.
Endoscopy, inserting a tube with a camera at the end, might be used to study structures within living animals. Endoscopy is performed either through the mouth or through the rectum, so the gastrointestinal tract is often the primary organ of interest.
There are also less invasive methods. For example, to study the blood vessels of living animals or humans, the scientist may insert an opaque dye into the animal that will highlight the circulatory system when imaging technology, such as angiography.
Techniques such as magnetic resonance imaging (MRI), computed tomography (CT), or x-ray also reveal information about the inside of a living body.
Medical and dental students perform dissection as part of their practical work in gross human anatomy during their studies. They may dissect a human corpse.
Students of gross anatomy will need to learn about the major body systems.
Human body systems
There are 11 organ systems in the human body: http://www.innerbody.com/
- The integumentary system, meaning skin, hair, nails, and so on
- Skeletal system
- Muscular system
- Lymphatic system
- Respiratory system
- Digestive system
- Nervous system
- Endocrine system, which regulates hormone production
- Cardiovascular system
- Urinary system
- Reproductive systems
Although these systems have different names, they all work interdependently, meaning they work together and depend on each other.
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.
By looking at tissue under the microscope, we can learn about the architecture of the cells, how they are put together, and how they relate to each other.
For example, if a person has cancer, examining the tissue under the microscope will reveal how the cancer cells are acting and how they affect normal human tissue.
This commonly involves studying tissues and cells using histological techniques such as sectioning and staining, and then looking at them under an electron or light microscope.
Sectioning involves 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 colors so they can be more easily distinguished when they are examined, especially if different structures are next to each other.
Histology is vital for the understanding and advancement of medicine, veterinary medicine, biology, and other aspects of life science.
Histology is used for:
Teaching: Histology slides are used in teaching labs to help students who are learning about the microstructures of biological tissues.
Diagnosis: Tissue samples, or biopsies, are taken from patients and sent to the lab for analysis by a histologist.
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.
Histotechnicians, also known as histology technicians, histology technologists, biomedical scientists, medical scientists, or medical laboratory technicians, work in histology laboratories.
These specialists use special skills to process samples of biological tissues that may come from patients, from suspects if it is a forensic lab, or from corpses. Using a series of techniques, they prepare tiny slices of tissue, known as sections. They mount the slices on slides and add histology stains. The slides are then examined by a histopathologist, or pathologist, for analysis.
The skills of a histologist must be meticulous and precise to deliver top-quality samples for examination under a microscope by histopathologist.
A pathologist is a medical doctor who has graduated from medical school and then goes on to specialize in pathology through their residency. Residency programs are required for all specialties, and for pathology, the training is an additional four years.
They examine cells and tissues and interpret what they see, so that they or others can use the data to decide on treatment for an illness, determine how somebody was injured or died, and so on.
Histopathology is a sub-discipline of pathology. It is the microscopic study of disease tissues and cells.
Most health-care related studies need training in gross anatomy and histology. Paramedics, physical therapists, occupational therapists, medical doctors, orthotists and prosthetists, and biological scientists all need a knowledge of anatomy.
Some websites offer a "tour" of the human body which explains the different organs and how they are made up. The National Institutes of Health offer a range of resources about the different parts of the body.