ANATOMY AND PHYSIOLOGY IWhat are Anatomy and Physiology?Anatomy:the word anatomy is derived from a Greek word “Anatome” meaning to cutup. It is the study of structures that make up the body and how those structures relatewith each other.The study of anatomy includes many sub specialties. These areGross anatomy,Microscopic anatomy, Developmental anatomyandEmbryology.Gross anatomystudies body structure without microscope.Systemic anatomystudiesfunctional relationships of organs within a system whereasRegional anatomystudiesbody part regionally. Both systemic and regional approaches may be used to studygross anatomyMicroscopic anatomy(Histology)requires the use of microscope to study tissues thatform the various organs of the body.Physiology: the word physiology derived from a Greek word for study of nature. It isthe study of how the body and its part work or function.Hence, Anatomy and physiology are studied together to give students a fullappreciation and understanding of human body.HomeostasisWhen structure and function are coordinated the body achieves a relative stability ofits internal environment calledhomeostasis/ staying the same. Although the externalenvironmental changes constantly, the internal environment of a healthy body remainsthe same with in normal limits.Under normal conditions, homeostasis is maintained by adaptive mechanisms rangingfrom control center in the brain to chemical substances called hormones that aresecreted by various organs directly into the blood streams. Some of the functionscontrolled by homeostasis mechanisms are blood pressure, body temperature,breathing and heart rate.1 |a n a t o m y a n d p h y s i o l o g y
Structural Organization of the Human BodyThe human body has different structural levels of organization, starting with atomsmolecules and compounds and increasing in size and complexity to cells, tissues,organs and the systems that make up the complete organism.Atoms molecules and compounds: - At its simplest level, the body is composed ofatoms. The most common elements in living organism are carbon, hydrogen, oxygen,nitrogen phosphorus and sulfur.Atoms → Molecule → CompoundsCell:The smallest independent units of life. All life depends on the many chemicalactivities of cells. Some of the basic functions of cell are: growth, metabolism,irritability and reproduction.Tissue:tissue is made up of many similar cells that perform a specific function. Thevarious tissues of the body are divided in to four groups. These are epithelial,connective, and nervous and muscle tissue.2 |a n a t o m y a n d p h y s i o l o g y
Epithelial tissue: -Found in the outer layer of skin, lining of organs, blood andlymph vessels and body cavities.