Gross anatomy divided into three different types:
- Surface anatomy (or superficial anatomy) is the study of external anatomical features without dissection.
- Regional anatomy focuses on specific external and internal regions of the body (such as the head or chest) and how different systems work together in that region.
- Systemic anatomy focuses on the anatomy of different organ systems, such as the respiratory or nervous system.
Regional anatomy is widely used in modern teaching because it is easier to apply to a clinical setting than systemic anatomy. The major anatomy textbook, Gray’s Anatomy, has recently been reorganized from a systems format to a regional format to reflect this preference. Surface anatomy is also widely used to gauge the position and structure of deeper organs, tissues, and systems.
The microscopic anatomy is divided into two subtype:
- Cytology, the study of the structure and function of cells
- Histology, the study of the organization and details of biological tissues
The human body has many layers of organization. Biological systems consist of organs that consist of tissues, and tissue in turn is made up of cells and connective tissue. Microscopic anatomy allows one to focus on these tissues and cells.
The total body water in adults of average build is about 60% of body weight. This proportion is higher in babies and in young adults. It is lower in old and obese people of all ages. About 22 % of body weight is extracellular, water and about 38% is intracellular water.
22% consists of blood, plasma, lymph, csf, and fluid in interstitial spaces of body. It is also present in synovial fluid, pericardial fluid, pleural fluid.
38% the composition of intracellular fluid is largely controlled by cell itself, because there are selective uptake and discharge mechanisms present in the cell membrane.
Example: Na (Sodium) levels are more in ECF than in ICF. This concentration is essential for function of excitable cells (Nerve & Muscle). Substance found in ICF are ATP, protein and potassium in higher concentrations.
The branch of life science, which deals with the study of cells in terms of structure, function and chemistry, is called cytology. It’s from Greek kytos,”a hollow” and logia “study of”.