BONES AND BONE TISSUES(学习资料).pptVIP

BONES AND BONE TISSUES CHAPTER 6 9/16/07 Introduction One of the most remarkable tissues of the human body Far from inert and lifeless, bones are living, dynamic structures Bones serve a wide variety of very diverse functions within us Noted for their strength and resiliency during life, bones will remain long after we are gone Chapter Outline Skeletal cartilages Bones Disorders of bones The skeleton throughout life Location and Basic Structure Cartilages are found throughout the adult human body Location and Basic Structure Initially our skeleton is made up of fast growing cartilages and fibrous membranes Gradually our skeletal cartilages are replaced by bone Upon reaching adulthood the skeleton becomes almost fully ossified Only a few cartilages remain in the adult skeleton Location and Basic Structure A typical cartilage is composed of connective tissue cartilage It contains no nerves or blood vessels It is surrounded by a layer of dense irregular connective tissue called the perichondrium which resists outward expansion of the tissue when subjected to pressure Location and Basic Structure Each type of cartilage contains a high proportion of water which makes them resilient after compression Cartilage is 60-80% water The water allows nutrients to diffuse rapidly through a loose matrix Basic structure, type location There are three types of cartilage tissue: hyaline, elastic, and fibrocartilage Each type consists of chondrocytes living in an extracellular matrix Each contains a matrix of jellylike ground substance of complex sugar molecules that attract and hold water that is laced with connective tissue fibers Hyaline cartilages The most prevalent type of cartilage Its high proportion of collagen fibers give it flexibility and resilience while providing support Upon examination the tissue appears white, frosted, and smooth Hyaline cartilages The chondrocytes appear spherical Each chondrocyte occupies a cavity in the matrix called a lacuna The only type