Date: Notes: The Skeletal System Humans have an endoskeleton that develops from of the mesoderm. Composed of o o o : connects bone-to-bone o : connects muscle-to-bone Functions: o o o o Divided into two main regions o Spine, rib cage, skull o Upper Appendages (extremities) Arms, hands, wrists Lower Appendages (extremities) Legs, feet, hips Characteristics of Skeleton : where two bones meet to make a joint : protrusions and edges on the bone o Sites of tendon and ligament attachment : large rounded projection : narrow prominent ridge : large, blunt, irregularly shaped process (Only found on the femur) Notes: Skeletal System Page 1
: small rounded projection or process : raised area above a condyl : sharp, slender, often pointed projection : any bony prominence o Projections that help form joints : bony expansion carried on a narrow neck : rounded articular projection : arm like bar of bone o Depressions and openings allowing blood vessels and nerve fibers to pass : canal like passage way : Cavity within bone filled with air and lined with mucous membrane : shallow basin like depression in bone : narrow, slit like opening : round or oval opening through a bone Axial Skeleton o Cranial Bones (skull cap) Cranial base o Facial bones o Held together by Skull Cranial Bones o : makes up the forehead and eyebrow ridges Upper part of the (eye sockets) Thicker area above the orbits is the Notes: Skeletal System Page 2
o : has a flat portion, along with : where neck muscles attach : attachment for neck & throat muscles : contain the ear bones : forms the cheek bone and articulates with the mandible o : helps protect brain o : posterior base of the cranium Formed of several bones that fuse and leave an opening called the attach the head to the vertebral column o Mandible: alveolus, body, condyle, and ramus Tooth Anatomy Crown: covered by (made of calcium) Vertebral Column Flexible column that Two major types of bone o (movable) vertebrae Vertebrae: supports the head and allows it to rotate Vertebrae Has two articulation points with the ribs; allows the ribs to flex for breathing Vertebrae Larger and thicker than other vertebrae Supports most of body s weight o (fixed) vertebrae Fused to one another; don t move : fuses with pelvis : tailbone; attachment point for muscles of the upper leg Notes: Skeletal System Page 3
(thorax): protective structure that also aids in breathing o True ribs: attach to sternum o False ribs: floating o Manubrium o Gladiolus o Xiphoid process: attachment for stomach muscles Appendicular Skeleton Superior extremities (upper appendages) o (collarbone): long bone that runs parallel to first rib Attachment for muscles of the arms, back, chest, and neck o (shoulder blade): flat bone, parallel to vertebrae Attachment for muscles that move the shoulders and arms o : largest bone of the upper arm o : shorter forearm bone; located thumb side o : longer forearm bone (elbow) : articulates with the humerus o : wrist bones o : form the palm of the hand o : finger bones Notes: Skeletal System Page 4
Inferior Extremities (lower appendages) Pelvic bone: o : forms the point of articulation with the femur o : passage for major blood vessels and nerves Leg bones o : longest and strongest bone of the body o (shin bone) o : smaller, lateral bone of the leg o (knee-cap) Foot bones o : forms ankle o : arch of the foot o : toes Bone Bone tissue is called Bone types (shape) o (femur, phalanges) o (carpals, tarsals) o (skull bones) o (vertebrae) o (patella) Notes: Skeletal System Page 5
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Bone Structure External : connective tissue that surrounds the bone o Important in, maintenance, and healing o Contains blood vessels and nerves providing the nutrition and nutrition o Where and attach : shaft : ends of bone; contain red marrow : found between diaphysis and epiphysis; long bone growth : covers the articular surface of bones Internal Features : rigid outer shell of the bone; 20% of structure, 80% of weight o : structural unit of compact bone tissue o canal: internal structure of osteon; blood vessels and nerves pass through here o : cell of bone tissue; secrete bone matrix Bone matrix composed of collagen fibers and osteocalcin (contain calcium salts) : cavities that store osteocytes Connect to each other and to blood vessels through. canals: carry blood vessels and nerves of the periosteum to the central Haversian canals (trabecular/ ) bone: forms the ends of the long bones and the center of the other bones; 80% structure; composed of honeycomb-like network bony struts; less dense and than compact Notes: Skeletal System Page 7
Joints o (marrow) cavity: hollow center of long bones; bordered by spongy bone and lined with a thin layer of connective tissue called (capable of generating new bone cells); filled with. : consists of fat cells; act as food reserve for bone cells : produces red blood cells II) Joints: some accompanied by a bursa that contains synovial fluid. A) Type of movement depends on 1) The manner in which the bones fit together 2) The tightness of fit between the articular surfaces 3) The tension f the tissues forming the articulation 4) The position of the ligaments, muscles, and tendons associated with the joints B) Structural 1) Cartilaginous: cartilage covers the articulating bone surfaces; example is the pubic bones 2) Fibrous: articulated bones are attached by fibrous connective tissue; example is between the radius and ulna 3) Synovial: articulating surfaceis coverd with a fluid-filled, fibrous, connective-tissue sack called the synovial capsule; examples are elbows and knees C) Functional 1) Synarthrosis: permit no movement; (a) Gomphosis: formed by a conical process; it is held in a socket by a ligament; teeth (b) Syndesmosis: formed when two bones are joined by one or more ligaments; example is the joint that holds together the tibia and fibula in the ankle region (c) Synchondrosis (symphysis) joints: two bones join together by a piece of cartilage; (d) Synostosis (sutures): formed by the fusion of two bones 2) Amphiarthrosis: slight movement 3) Diarthrosis: provide variety of movements; synovial joints : wide array of movements; like the hip and shoulder (ellipsoid): occurs where a ball-like articular surface rests against the curve-shaped end of the another articular surface; examples: knee between radius and carpals : side-to-side movements; carpals : permit angular motion along one plane; example: elbow, knee, ankle joint : allows a rotation; example: invertebral joints : resemble a saddle in which one articular surface rocks back and forth upon another; joint of thumb Notes: Skeletal System Page 8
Bone Growth Bone-forming cells (osteoblasts and osteoclasts) move into the cartilage pegs helping to sculpt growing bones Build bone tissue break down bone and cartilage; carve & sculpt bone Process osteoclasts in the center of the cartilage pegs begin to entering the cavity, for bone growth and maintenance enter and start secreting the bone tissue to. is deposited first, then converted into as the cavity enlarges Homeostatic Imbalance a break in the bone bone penetrates through the skin bone does not penetrate skin Notes: Skeletal System Page 9
Fracture Treatment When a physician pulls on bone to realign bone ends When a physician surgically inserts pins or wires to realign bones How would damage to the components affect function? Shin Splint: a painful condition of the that develop from overuse of the ; NOT the same as a Bone and Joint Problems Arthritis: a condition causing and in the. Osteoarthritis: deterioration of the covering the ends of bones Notes: Skeletal System Page 10
: a condition in which the immune system attacks connective tissues Ankylosing spondylitis: arthritis that affects the ; causes the fusion of the vertebrae arthritis: arthritis that affects children Organ-System Diseases Gout: a metabolic disorder that causes build-up of throughout body Systemic Lupus erythematosus: an autoimmune disease and. : connective tissue disorder that causes thickening of skin and abnormal growth of connective tissues; autoimmune disease : disorder that causes widespread joint pain; no degeneration of tissues patients look normal. Bone Degradation Osteoporosis: degenerative bone disorder; can occur at any age o Causes: or undernutrition (not enough calcium-rich foods or vitamin D) Decreased levels of Smoking Excessive alcohol consumption o A less severe case is. Tooth decay: tooth destruction caused by. o Enzymes created by bacteria remove, and break down of tooth leading to a. o Advanced tooth decay leads to teeth loss and destruction of underlying jawbone structure Notes: Skeletal System Page 11
Myeloma: a cancer of ; weakens the immune system o Most common treatment is chemotherapy with. Osteomyelitis: inflammation of the bone caused by. Osteonecrosis: a condition caused by due to the of blood flow Aging of the Skeletal System Bone is regularly broken down as new bone is added Rate of bone production is greater in young people bones are denser, heavier, and larger As we grow older, the bone rebuilding activity of the. One solution: hip replacement Notes: Skeletal System Page 12