anatomy chapter 1 anatomical regions (chapter 1).ppt

The Human Body: Anatomical Regions, Directions, and Body Cavities

Credit: Carlos J Bidot Author 2006Revised 2010

Overview of Anatomy and PhysiologyAnatomy the study of the structure of body parts and their relationships to one anotherGross or macroscopicMicroscopicDevelopmentalPhysiology the study of the function of the bodys structural machinery

Gross AnatomyRegional all structures in one part of the body (such as the abdomen or leg)Systemic gross anatomy of the body studied by systemSurface study of internal structures as they relate to the overlying skin

Microscopic AnatomyCytology study of the cell

Histology study of tissues

Developmental AnatomyTraces structural changes throughout life

Embryology study of developmental changes of the body before birth

Specialized Branches of AnatomyPathological anatomy study of structural changes caused by disease

Radiographic anatomy study of internal structures visualized by X ray

Molecular biology study of anatomical structures at a sub-cellular level

PhysiologyConsiders the operation of specific organ systemsRenal kidney functionNeurophysiology workings of the nervous systemCardiovascular operation of the heart and blood vesselsFocuses on the functions of the body, often at the cellular or molecular level

Levels of Structural Organization

Chemical levelAtoms combine to form molecules1234Cellular levelCells are made up of moleculesTissue levelTissues consist of similar types of cells5Organ system levelOrgan systems consist of different organs that work together closelyOrgan levelOrgans are made up of different types of tissues6Organismal levelThe human organism is made up of many organ systemsAtomsMoleculesSmooth muscle cellSmooth muscle tissueConnective tissueSmooth muscle tissueEpithelial tissueBlood vessel (organ)HeartBlood vesselsCardiovascular systemFigure 1.1

Levels of Structural OrganizationChemical atoms combined to form moleculesCellular cells are made of moleculesTissue consists of similar types of cellsOrgan made up of different types of tissuesOrgan system consists of different organs that work closely togetherOrganism made up of the organ systems

HomeostasisHomeostasis is the ability to maintain a relatively stable internal environment in an ever-changing outside worldThe internal environment of the body is in a dynamic state of equilibriumChemical, thermal, and neural factors interact to maintain homeostasis

Homeostatic ImbalanceDisturbance of homeostasis or the bodys normal equilibriumOverwhelming of negative feedback mechanisms allowing destructive positive feedback mechanisms to take over-possible disease,death

Anatomical PositionBody erect Feet slightly apartPalms facing forward Thumbs point away from body

Figure 1.7a

Directional TermsSuperior and inferior toward and away from the head, respectivelyAnterior and posterior toward the front and back of the bodyMedial, lateral, and intermediate toward the midline, away from the midline, and between a more medial and lateral structure

Directional TermsProximal and distal closer to and farther from the origin of the body

Superficial and deep toward and away from the body surface

Directional Terms

Table 1.1

Directional Terms

Table 1.1

Regional Terms: Anterior ViewAxial head, neck, and trunkAppendicular appendages or limbsSpecific regional terminology

Figure 1.7a

Regional Terms: Posterior View

Figure 1.7b

Body PlanesSagittal divides the body into right and left partsMidsagittal or medial sagittal plane that lies on the midlineFrontal or coronal divides the body into anterior and posterior partsTransverse or horizontal (cross section) divides the body into superior and inferior partsOblique section cuts made diagonally

Body Planes

Figure 1.8

Anatomical VariabilityHumans vary slightly in both external and internal anatomyOver 90% of all anatomical structures match textbook descriptions, but:Nerves or blood vessels may be somewhat out of placeSmall muscles may be missing Extreme anatomical variations are seldom seen

Body Cavities

Figure 1.9a

Body CavitiesDorsal cavity protects the nervous system, and is divided into two subdivisionsCranial cavity is within the skull and encases the brainVertebral cavity runs within the vertebral column and encases the spinal cordVentral cavity houses the internal organs (viscera), and is divided into two subdivisions: - Thoracic and Abdominopelvic cavities

Body Cavities

Figure 1.9b

Body CavitiesThoracic cavity is subdivided into pleural cavities, the mediastinum, and the pericardial cavityPleural cavities each houses a lungMediastinum contains the pericardial cavity, and surrounds the remaining thoracic organsPericardial cavity encloses the heart

Body CavitiesThe abdominopelvic cavity is separated from the superior thoracic cavity by the dome-shaped diaphragmIt is composed of two subdivisionsAbdominal cavity contains the stomach, intestines, spleen, liver, and other organsPelvic cavity lies within the pelvis and contains the bladder, reproductive organs, and rectum

Ventral Body Cavity MembranesParietal serosa lines internal body walls

Visceral serosa covers the internal organs

Serous fluid separates the serosae (A serous membrane, especially one that lines the pericardial, pleural, and peritoneal cavities, enclosing their contents)

Ventral Body Cavity Membranes

Figure 1.10a

Ventral Body Cavity Membranes

Figure 1.10b

Other Body CavitiesOral and digestive mouth and cavities of the digestive organsNasal located within and posterior to the noseOrbital house the eyesMiddle ear contain bones (ossicles) that transmit sound vibrationsSynovial joint cavities

Abdominopelvic RegionsUmbilicalEpigastricHypogastricRight and left iliac or inguinalRight and left lumbarRight and left hypochondriac

Figure 1.11a

Organs of the Abdominopelvic Regions

Figure 1.11b

Abdominopelvic QuadrantsRight upper (RUQ)Left upper (LUQ)Right lower (RLQ)Left lower (LLQ)

Figure 1.12