Exercise 8 - Overview of the Skeleton: Classification and Structures of Bones and Cartilages

is constructed of two of the most supportive tissues found in the human body - cartilage and bone

bones that lie around the body's center of gravity

bones of the limbs, or appendages

hyaline cartilage covers the bone ends at movable joints and the epiphyseal surface in place of the periosteum

strips of cartilage associated with the rib bones, found connecting the ribs to the sternum (breastbone) and are made from hyaline cartilage and provide flexibility to the chest cavity, as well as protection to the organs in the upper torso

largely construct the larynx (voice box)

reinforce other passageways of the respiratory system

support the external nose

typically consists primarly of water and is fairly resilient, are also distinguished by the fact that they contain no nerves and very few blood vessels

fibrous, connective tissue membrane covering the external surface of cartilaginous structures, acts to resist distortion of the cartilage when it is subjected to pressure, and plays a role in cartilage growth and repair

cushion the vertebrae and absorbs shock

• provides sturdy support with some resilience or "give"
• LOCATION: nose, trachea, larynx, and in the connection between the ribs and the breastbone and also the ends of bone where they form joints

• is much more flexible than hyaline cartilage and tolerates repeated bending better
• LOCATION: external ear and epiglottis

• consists of row of chondrocytes alternating with rows of thick collagen fibers, has great tensile strength, can withstand heavy compression, and is used to construct the intervertebral discs and the cartilages within the knee joint
• LOCATION: pubic symphysis, intervertebral discs, and meniscus of the knee

looks smooth and homogenous

is composed of small trabeculae (bars) of bone and lots of open space

are much longer than they are wide, generally consisting of a shaft with heads at either end and composed predominantly of compact bone, ex: femur and phalanges

are typically cube-shaped, and contain more spongy bone than compact bone, ex: tarsals and carpals

are generally thin, with two waferlike layers of compact bone sandwiching a layer of spongy bone between them, ex: bones of the skull

have complicated shapes that fit none of the preceding classes, ex: vertebrae and hip bones

are special types of short bones formed in tendons, ex: patella (kneecaps)

tiny bones between cranial bones

reveal where bones form joints with other bones, where muscles, tendons, and ligaments were attached, and where blood vessels and nerves passed

elongated shaft of a long bone

double-layered connective tissue that covers and nourishes the bone

many fibers of the periosteum which penetrate into the bone

the end of a long bone, attached to the shaft

plate of hyaline cartilage at the junction of the diaphysis and epiphysis that provides for growth in length of a long bone

are replaced with bone and appear as thin, barely discernible remnants

a storage region for adipose tissue

is found in the marrow cavities to form blood cells

connective tissue membrane covering internal bone surfaces

the canal in the center of each osteon that contains minute blood vessels and nerve fibers that serve the needs of the osteocytes

mature bone cells

a small space, cavity, or depression; lacunae in bone or cartilage are occupied by cells

one of the tubular layers of bone surrounding the central canal in an osteon

system of interconnecting canals in the microscopic structure of adult compact; unit of bone; also called Haversian system

tiny canals radiating outward from a central canal to the lacunae of the first lamella and then form lamella to lamella

a small cavity within the bone matrix, containing an osteocyte

run into the compact bone and marrow cavity from the periosteium, at right angles to the shaft

embryonic formation of bone by the replacement of calcified cartilage; most skeletal bones are formed by this process (hyaline cartilage)

extracellular matrix layer between osteocytes runs in compact bone