COLLEGE PHYSICSChapter # Chapter TitlePowerPoint Image SlideshowANATOMY & PHYSIOLOGYChapter 4 THE TISSUE LEVEL OF ORGANIZATIONPowerPoint Image Slideshow
FIGURE 4.1Micrograph of Cervical TissueThis figure is a view of the regular architecture of normal tissue contrasted with theirregular arrangement of cancerous cells. (credit: “Haymanj”/Wikimedia Commons)
TISSUESThe termtissueis used to describe a group of cells foundtogether in the body. The cells within a tissue share acommon embryonic origin.Although there are many types of cells in the human body,they are organized into four broad categories of tissues:epithelial, connective, muscle, and nervous.Each of these categories is characterized by specificfunctions that contribute to the overall health andmaintenance of the body. A disruption of the structure is asign of injury or disease. Such changes can be detectedthroughhistology, the microscopic study of tissueappearance, organization, and function.
TYPES OF TISSUESEpithelial tissue, also referred to as epithelium, refers to thesheets of cells that cover exterior surfaces of the body, linesinternal cavities and passageways, and forms certain glands.Connective tissue, as its name implies, binds the cells andorgans of the body together and functions in the protection,support, and integration of all parts of the body.Muscle tissueis excitable, responding to stimulation andcontracting to provide movement, and occurs as three majortypes: skeletal (voluntary) muscle, smooth muscle, andcardiac muscle in the heart.Nervous tissueis also excitable, allowing the propagation ofelectrochemical signals in the form of nerve impulses thatcommunicate between different regions of the body
FIGURE 4.3Embryonic Origin of Tissues andMajor Organs
TISSUE MEMBRANESAtissue membraneis a thin layer or sheet of cellsthat covers the outside of the body (for example, skin),the organs (for example, pericardium), internalpassageways that lead to the exterior of the body (forexample, abdominal mesenteries), and the lining of themoveable joint cavities. There are two basic types oftissue membranes: connective tissue and epithelialmembranes
FIGURE 4.4Tissue MembranesThe two broad categories of tissuemembranes in the body are (1)connective tissue membranes, whichinclude synovial membranes, and (2)epithelial membranes, which includemucous membranes, serousmembranes, and the cutaneousmembrane, in other words, the skin.