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skeletal system CHAPTER 6

Skeletal System
1.provides structure/shape for body
2.protects inner organs
3. works as levers to move body (also needs muscle)
4.mineral storage, calcium (Ca), phosphorous can release Ca to maintain blood level.
5.Contains red bone marrow
6. hematopoesis production of blood cells, RBC's, WBC's, and platelets.
Functions of the Skeleton
1.provides structure/shape for body
2.protects inner organs as levers to move body(also need muscle)
4.mineral storage calcium and phosphorous can release calcium to maintain blood level.
5.contains red bone marrow
6.hemotopoesis production blood cells (RBC's,WBC's, and platelets).
Types of Bone Tissues
1.mature calcified hard bone cells.
2. made up calcium salts and collagen
3. most times when calcium is taken from bones it is replaced by the same amount. Old bone (digested or broken down) by osteoclasts.

1. calcified bone tissue found just under the periosteum i(pic on pg 115) of long bones
2. has haversian system they tunnel through the bone bringing blood and nutrients (pic pg 115) red is always artery and blue is always vein!! They have both of these
1.web like bone tissue part of bone tissue has been dissolved found inside compact bone haversian systems

1.cartilage found in the epiphyses and joint surfaces
2shock absorber where bone meets at joints

1.tough fibrous outer covering of bones
2. its an anchor

MEDULLARY CANAL opening in the center of the diaphysis

1.lines the inside of the medullary canal.
Long bone
1.has a diaphysis or the shaft, epiphysis the ends that contain the growth plate
2.largest and strongest as levers to move body.
4.contain both red and yellow bone marrow, more red in children and gets more yellow as we get older.
5.where bone growth takes place
6.femur is the largest long bone, humerus, radius, ulna, feet, and hands but not ankles or wrist.

YELLOW BONE MARROW:1. composed mostly of fat adipose cells. 2. is found in the medullary canal of long bone 3. found in adult bones

RED BONE MARROW 1. found primarily in flat bones, but also a small amount in the epiphysis of long bones.2. responsible for hemopotesis (rbc production).3. found in childs bone.

2.increase joint strength and mobility
3.these are metacarpals,metatarsals, and phylanges

1.contains most of the red bone marrow
2.contain no yellow marrow
3.the crainium, sternum, ribs, shoulder blades (scapula), hips

1.irregularly shaped
2.all other bones
3.examples are vertebrae, facial bones, auditory ossicles(bones that make up middle ear)
1. is bone development
2.cartilage is a pre cursor to bone
3.requires calcium, phosphorous,vitamin d, and protein
4.calcium deposits increase the strength of bones
5. more exercise equals more calcium deposits.
6.long bones grown to increase height
7.ossification of the fetal skeleton begins in the 3rd month of gestation
8.crainial and facial bones are first made of fibrous connective tissue, then replacement by bone radiates from a center of ossification in each bone (starts in middle and works its way out)
9. osteoblasts create new bone cells.
10.osteoclasts are large bone cells that digest(break apart) old bone tissue. birth there are area of fibrous connective tissue remaining between the bones of the crainum called fontanels. This allows bones to overlap during birth and should close by the age of 2.
12. epiphyseal disc or plate: is a cartilage area located between the epiphysis and diaphysis of long bones of children. Growth can occur in this area until early 20's when the epiphyseal disc closes or calcifies.
factors that affect bone growth and maintenance
1.heredity:each persons genetics has already determined how tall they will be.
2.Nutrition:they need calcium,phosphorous,protein,and vitamin D. Vitamin D is needed for the absorption of calcium and phosphorous in the small intestines.Need vitamins A and C they are needed for the calcification of new bones.
3.Hormones:a graph on table 6-1 page 120.
4.Exercise or Stress:without baring weight the bones will lose calcium faster than it can replace it,walking is a good way to do this. The more exercise the stronger the bones due to more matrix deposits ( deposits of calcium and phosphorous).Those patients bedridden bones will become more fragile as they lose their matrix.
Axial Skeleton
Axial Skeleton:
is the core skeleton, made up of 80 bones. Makes up the skull, facial bones, rib cage, and spine.
Appendicular Skeleton
Appendicular Skeleton: The bones or arms, legs, shoulder,and pelvic girdle.
the crainial bones form the brain case.
the facial bones support the face.
the joints are immovable,they are called sutures.
1st bone: is frontal (forehead)
2nd bone: is parietal (roofs and sides)
3rd bone: is occipital (base of the skull)
4th bone: is temporal (just above ears on each side, helps protect the ossicles) ossicles=bones inside the ears.
5th bone:sphenoid (is inside resembles a bat, all other cranial bones attach to it.)
6th bone:is ethnoid and it is located between the eyes.
7th bone is:hyoid it is where the tongue attaches.
8th bone is: sutrues lines that form junctions between cranial bones.
9th bone:is the fontanels the membranous openings in cranial bones of newborns and the bones grow together.
Facial Bones
Facial Bones
1.maxilla:upper jaw
2.madile:lower jaw
3. nasal cavity:it is created by 3 nasal bones. 1st is the nasal bones and you have 2 of those, the bridge of your nose. 2nd is vomer you have 1 of these, the lower part of the nasal cavity, it creates a midline or the nasal septum
3rd bone:inferior concha:they are the sides of the nasal cavity.
4.lacrimal:inner aspecs of the eye socket contains tear ducts.
5.Zygomatic:forms the cheecks and contains the sinuses
6.Auditory Ossicles:they are 3 tiny bones in each ear, not attached to any other bones.the 3 bones are 1.mallues:its hammer shaped. 2.incus:its anval shaped. 3.stapes:stirrup shaped.
Cervical Vertebrae:top part of spine there are 7 of them and they are located in the neck. (1) atlas first cervical vertebra articulates with occipital bone allows up/down(nodding) movements.(2)axis 2nd vertical vertebra articulates with the atlas, allows side to side or turning movement.
Thoracis Vertabrae: there are 12 of these they are located in chest area,upper back, and articulate with the ribs.
Lumbar: 5 of these, lower back, primary weight baring vertebrae.
Sacrum:5 of these, individual bones in a child, one fused bone in adults.It forms the pelvic girdle and articulates with the hips.
Coccyx: 4 of these they are 4 individual bones in a child and one fused in an adult, this is your tail bone.
Foramen:the opening in the center of the vertebra for the spinal cord.
Spinous:is a transverse process, projections that attach to muscles that bend the vertebral column.
Disc:fibrous cartilage they separate the bodies of the adjacent vertebrae that cushion,and act as shock absorbers as we walk.
There are 4 natural curves that center the skull over the body. (1) Cervial Curve (2) Thoracic Curve
Rib Cage
Rib Cage: it consists of sternum and 12 pairs of ribs. Protects lungs, heart, and spleen.
True Ribs: there are 7 on each side, attach to front to the sternum, and in back to the vertebrae.
False Ribs: there are 3 on each side. They attach to the 7th rib and the vertebrae..
Floating Ribs: there are 2 on each side, and they attach only to the vertebrae.
Rib Cage
Costal Cartilage: Attaches ribs to the sternum.
Sternum:Also known as the breast bone. There are 3 parts to it. (1) is manubrium: the upper portion (2) body: the middle portion (3)Xiphoid Process: is the lower portion and is made of cartilage. pics on page 132
Appendicular Skeleton
APPENDICULAR SKELETON: made up of 126 bones
Shoulder Girdle: the scapula also known as shoulder blade, its triangular shaped.
Acromoin Process:a projection from the spine of the scapula.
Clavicle:known as the collar bone.
Appendicular Skeleton
Humerous:upper arm, 2nd largest long bone in body
Radius:in forearm on thumb side, and rotates around the ulna
Ulna:is larger than the radius,makes up elbow
Olecranon Process:part of ulna that forms the elbow
Carpals:they are wrists bones
Metacarpals:they are hand bones.
Phalanges:they are the finger bones.
Appendicular Skeleton
Ilium:upper or flared bones in the back.
Iliac Crest:top ridge of the ilium.
Ischium:lower portion in back
Acetabulum:cavity in the ischium that forms the hip socket.
Pubic:the bone in the front
Symphysis Pubis:the area where pubic bones meet.
(symphysis a place where 2 bones meet)
Appendicular Skeleton
Femur:the largest and the strongest
Patella:is the knee cap
Tibia:in lower leg, larger of the 2 bones in the lower leg.
Fibula:is in the lower leg, and the smaller bone
Tarsals:ankle bones (1)calcaneus the tarsal that makes the heel of the foot.(2)talus:tarsal that articulates with the tibia and fibula
Metatarsals:bones of the foot, the little square ones.
Phanlanges:are the toes, these make up the fingers and toes.
JOINTS:classified according to amount of movement permitted (table 6-5 on page 138). They are the articulations of bones(where bones meet)
Types of Joints
Types of Joints
Ball and Socket:it is the greatest freedom of movement found in hip and shoulder.
Hinge:allows movement in one direction. Can be seen in the knee and elbow.
Pivot:allows rotation, the axis/atlas and radius/ulna do this.
Gliding:nearly flat and allow gliding movement. found in vertebrae, tarsals(wrists), and carpals(ankles)
Condyloid:movement in one direction with some lateral movement.found in tempora bone and madible.
Saddle:movement in several directions. example is the thumb.
Types of Joints
Types of joints cont....
Synarthrosis:non-moveable joints, connected by tough fibrous tissue that does not allow movement.ex:crianial sutures.
Amphiarthroses:partially moveable joints,cartilage between articulating surfaces, that allows a small amount of movement. ex:ribs to vertebra and sternum, down below the symphysis pubis.
Diarthroses:freely moveable joints all with synovial joints.
Articular Cartilage:is a cushion where 2 bones meet.
Bursa:joint capsule
Synovial Cavity:joint cavity between articular cartilage of 2 bones contains synovial fluid for lubrication.
Ligaments:connects bones at the joint.
Joints Movements
Movements (JOINTS)
Flexion:decreased angle brings 2 bones closer together
Extension:increase angle straightening motion.
Abduction:movement away from midline
Adduction:movement towards the midline
Rotation:is movement around the central axis, such as saying now, or rotating the lower arm.
Circumduction:it is a circular movement
Pronation:palms face back or down towards the bed.
Supination:palms face foreward such as anatomical positionon or up.
Inversion:to turn in
Eversion:is to turn out
Plantar Flexion:extend ankle joint pushing toes away from ankles(pointing toes)
Dorsiflexion:flex ankle joint of foot pulling toes toward the ankle.
Fractures(broken bones)
1.greenstick:incomplete and common in children
2.simple:closed no break in skin.(skin still intact)
3.compound:open out of place, and breaks the skin
4.comminuted:splinters or breaks into multiple pieces
5.Dislocation:bone displaced from the joint
Sprain:ligaments are torn but join isn't dislocated.
6.Arthritis:inflammation of joints that causes pain.
7.Herniated Disc:cartilage disc located between vertebrae protrudes out of place.
8.Ricketts:insufficient Vitamin D,bones become soft due to lack of calcification.
Spinal Curvature:page 132
1.kyphosis:hunch back outward curve in thoracic area
2.lordosis:a sway back,inward curve in lumbar area
3.scoliosis:side to side curve of spine, may appear S in shape.
Osteoporosis:pg 121 it is the weakening of bones,due to insufficient calcium and exercise, loss of bone mass, meaning more bone tissue is lost than made.
Osteomyelitis:infection of bone tissue.
Osteosarcoma:is bone cancer
Bone Markings
1.Process:projection from a bone
2.Condyles:knobs found at ends of long bones that create the articulation.
3.Head:the rounded end of long also creates the articulation
4.Neck:smaller area below the head of the bone
5.Trochanter:the large process on the femur
6. Crest:ridge or edge of a bone
7.Foramen:hole for the passage of blood vessels
8. Fossa:indention or pit
9.Notch:a deep indention or pit
10.Sinus:cavity or open space.
11.Proximal:closer to the trunk of the body
12.Distal:is further from the trunk of body.