Skeletal System 1

• 1. Axial
• 2. Apendicular

• All the bones through the midline of the body.
• 80 bones

• Upper & lower limbs (extremities or appendages), plus the bones forming the girdles that connect the limbs to the axial skeleton.
• (appendic = to hang on to)
• 126 bones

• 206
• (all articulate except for Hoid bone)

• 1. movement
• 2. support
• 3. protection
• 4. hemopoesis (RBC/WBC/Platelets)
• 5. mineral homeostasis (Ca++, PTH - chemo receptors)
• 6. energy storage (yellow marrow in shaft of long bone - attipose tissue)

• 1. compact bone
• 2. spongy bone

• 1. contains few spaces
• 2. strongest form of bone tissue
• 3. found beneath the periosteum of all bone
• 4. makes up the bulk of the diaphyses of long bone

repeating structural units called osteons or haversian system

concentric lamellae arranged around a central canal or haversian canal.

• circular plates of mineralized extracellular matrix of increasing diameter, surrounding a small network of blood vessels and nerves located in the central canal
• these tubelike units of bone generally form a series of parallel cylinders that, in long bones, tend to run parallel to the long axis of the bone.

growth rings of a tree

• does not contain osteons
• always located in the interior of a bone, protected by a covering of compact bone. consists of lamellae that are arranged in an irregular pattern of thin columns called trabeculae.

red bone marrow in bones that produce blood cells, and yellow bone marrow (adipose tissue) in other bones

numerous small blood vessels that provide nourishment to the osteosytes

unspecialized bone stem cells. only bone cells to undergo cell division; the resuting cells develop into osteoblasts.

• blasts -> build
• bone building cells. synthesize and secrete collagen fibers and other organic components needed to build the extracellular matrix of bone tissue, and they initiate calcification.

• mature bone cells, are the main cells in bone tissue and maintain its daily metabolism. ie exchange of nutrients & waste with the blood.
• no cell devision

• clasts -> breakdown
• huge cells
• concentrated in the endosteum - on the side that faces the bone surface - deeply folded into a ruffled border. Causes RESORPTION.

have a spce called a synovial cavity or joint cavity between the articulating bones. classified functionally as freely movable. bones at a synovial joint are covered by a layer of hyaline cartilage called articular cartilage.

RELEASE POWERFUL LYOSOMAL ENZYMES & ACIDS BY THE OSTEOCLATS THAT DIGEST THE PROTEIN AND MINERAL COMPONENTS OF THE UNDERLYING EXTRACELLULAR BONE MATRIX. Part of the normal development, maintenance, and repair of bone.

• 1. longbone
• 2. shortbone
• 3. flat bone
• 4. irregular
• 5. sesamoid

• (shaped like a sesame seed) develop in certain tendons where there is considerable friction, tension, and physical stress, such as the palms and soles.
• (exception - platellae)

fibrous join composed of a thin layer of dense irregular connective tissue; occur only between bones of the skull.

• process
• trochanter
• meatus
• fossa
• succas
• condyle
• crest
• tubeseal

• narrow slit between adjacent parts of bones through wh/ blood vessels or nerves pass
• superior orbital fissure of sphenoid bone

• opening through wh/ blood vessels, nerves or ligaments pass
• optic foramen of sphenoid bone

• shallow depression
• coronoid fossa of humerus

• furrow along bone surface that accommodates blood vessel, nerve, or tendon
• intertubercular sulcas of humerous

• tubelike opening
• external auditory meatus of temporal bone

• large, round protuberance with a smooth articular surface at end of bone
• lateral condyle of femur

• smooth, flat, slightly concave or convex articular surface
• superior articular facet of vertebra

• usually rounded articular projection supported on neck (constricted portion) of bone
• head of femur

• prominent ridge or elongated projection
• illiac crest of hip bone

• typically roughened projection above condyle
• medial epicondyle of femur

• long, narrow ridge or border (less prominent than crest)
• linea aspera of femur

• sharp, slender projection
• spinous process of vertebra

• very large projection
• greater trochanter of femur

• variably sized rounded projection
• greater turbercle of humerous

• variably sized projection that has a rough, bumpy surface
• ischial tuberosity

• hyaline
• elastic
• fibro

• found on many joint surfaces. pearly blueish in color w/ firm consistency & has a considerable amt of collagen. no nerves or blood vessels, & its structue is relatively simple.
• (hyaline: transparent)

• contains predominantly elastic fibers w/ fibroblasts between them; unstained tissue is yellowish.
• lung tissue, walls of elastic arteries, trachea, bronchial tubes, true vocal cords, suspensory ligaments of penus, some ligaments between vertebrae
• allows stretching between organs; is strong & can recoil to original shape after being stretched. Elasticity is important to normal functioning of lung tissue (recoils in exhaling) & elastic arteries (recoil between heartbeats to help maintain blood flow).

• has chondrocytes among clearly visible thick bundles of collagen fibers within extracellular matrix; lacks perichondrium
• pubic symphysis (where hip bones join anteriorly), intervertebral discs, menisci (cartilage pads) of knee, portions of tendons that insert into cartilage.
• support and joining structures together. strength & rigidity make it the strongest type of cartilage.

• interstitial (shondrocytes devide + laydown matric (GS elongatesthe cartilage)
• appositionally
• SEE NOTES....

• displaced
• complete or incomplete
• stress

• reactive stage: formation of fx hematoma
• reparative phase 1: fibrocartilaginous callus formation
• reparative phase 2: bony callus formation
• bone remodeling

fibrous joint composed of thin layer of dense irregular connective tissue; occur only between bones of the skull.

• 1. cervical (7)
• 2. thoracic (12)
• 3. lumbar (5)
• 4. sacral (1)
• 5. coxcx (1)

mesenchyme-filled spaces between cranial bones that are present at birth.

• 1. posterior
• 2. posterolateral
• 3. anterior
• 4. anterolateral

• 1. fibrous
• 2. cartilaginous
• 3. synovial

bone's shaft or body - the long, cylindrical, main portion of the bone

proximal & distal ends of the bone

• regions between the diaphysis & the epiphyses. 
• in a growing bone it contains
• epiphyseal (growth) plate, a layer of hyaline cartilage that allows the diaphysis of bone to grow in length
• (when bone ceases to grow in length the cartilage in the plate is replaced by bone (epiphyseal line)

bone structure that replaces the cartilage in the growth plate when bone ceases to grow in length

• thin layer of hyaline cartilage covering the part of the epiphysis where the bone forms an articulation (joint) with another bone.
• reduces friction
• absorbs shock
• (because it lacks a perichondrium and blood vessels, repair of damage is limited)

• hollow, cylindrical space within the diaphysis that contains fatty yellow bone marrow and numberous blood vessels in adults.
• * minimizes wt of bone by reducing the dense bony material where it is least needed.
• * long bones tubular design provides max strength w/ min wt.

• thin membrane that lines the medullary cavity.
• contains singly layer of bone-forming cells & a small amt of connective tissue.