What to Study for Chapter 5: Skeletal System Test

Bone Structure and Function

  1. Draw and label the structure of long bones.

  1. Endosteum
  2. Periosteum
  3. Yellow Marrow
  4. Red Marrow
  5. Compact Bone
  6. Sharpey’s Fibers
  7. Arteries
  8. Epiphysis
  9. Diaphysis
  10. Medullary Cavity
  11. Adult – yellow marrow
  12. Infant – red marrow
  13. Condyles
  14. Foramen

  1. Functions of the skeletal system
  2. Protection of internal organs – Mainly the bony thorax (ribs, sternum, thoracic vertebrae) and the cranium which houses the brain
  3. Storage of minerals – Mostly the calcium stored in the bones
  4. Erythropoiesis – formation of blood cells within the red bone marrow.
  5. Providing structure – forms the entire structure of the body
  6. Bone Classification (shape and function)
  7. Long – compact bone surrounding the medullary cavity in the diaphysis, spongy bone in the epiphysis
  8. Short – thin layer of compact bone surrounding spongy bone. Cube shaped
  9. Flat – thin layers of compact bone surrounding spongy bone. Flat and usually curved.
  10. Irregular – do not fit into the normal classification of bone shapes. Specialized bones
  11. Function of:
  12. Osteoclasts – break down osseous material
  13. Osteoblasts – builds osseous material

The Skull

Structures, function and location (include projections and processes)

  1. Frontal bones – forms the forehead, flat bone, protects the frontal lobe of the brain, anterior portion of the cranium.
  2. Parietal Bones – posterior to the frontal bone (coronal suture), Superior to the temporal bone (squamous suture). Protect the parietal lobe of the brain.
  3. Temporal Bones – Inferior to parietal bones, External auditory meatus (ear canal), Styloid process, mastoid process, jugular foramen, carotid foramen, zygomatic process.
  4. Sphenoid Bones – butterfly shaped bone that is anterior to the temporal bones and deep to the zygomatic process. Forms the superior walls of the nasal cavity and the medial walls of the eye orbit.
  5. Occipital Bones – Most posterior bone of the cranium. Joins the parietal bones at the lambdoid suture. Protects the occipital lobe of the brain. Foramen magnum (spinal cord goes through this)
  6. Lacrimal Bones – forms the anterior medial portion of the eye orbit. Has canals that drain tears into the nasal passage.
  7. Mandible Bone – largest and longest bone of the face, articulates with the temporal bone at the mandibular condyle, contains the bottom teeth
  8. Maxilla Bones – (2) forms the upper jaw, contains upper teeth, forms the inferior portion of the eye orbit, all facial bones articulate with the maxilla bones, forms the bony palate of the buccal cavity.
  9. Nasal Bones – rectangular bones that form the bridge of the nose
  10. Zygomatic Bones – “cheek” bones, articulate with the temporal bones at the zygomatic process.
  11. Glenoid Process – or “glenoid fossa”, the indentation of the scapula where the humerus articulates with the scapula.

Lower Extremities

Structure, function and location (include projections and processes)

  1. Coxal Bones – “hip bones”, formed from three bones, Ilium, Ischium, and Pubis
  2. Ilium – superior bone of the coxal bones, superior edge is iliac crest
  3. Ischium – inferior bone of the coxal bones, posterior edge is ischial spine
  4. Pubis – anterior bone of the coxal bones, join at the pubic symphysis
  5. Sacrum – 5 vertebral bones fused together to form the posterior portion of the pubic region
  6. Acetabulum – deep socket in the coxal bones where the femur articulates within the hip
  7. Femur – longest and strongest bone of the body. Forms the superior leg, articulates with the tibia to form the knee joint. Has lateral and medial condyle at distal end and femoral head at proximal end
  8. Tibia – proximal end articulates with the femur at knee joint. Distal end articulates with talus at the ankle joint. Medial bone of the lower leg.
  9. Fibula – lateral bone of the lower leg. Distal end articulates with the talus to form the lateral portion of the ankle joint.
  10. Tarsals – short bones that form the ankle.
  11. Metatarsals – long bones that form the main portion of the foot. Numbered 1-5 starting with the big toe.
  12. Proximal Phalanges – long bones of the toe closest to the foot.
  13. Medial Phalanges – Intermediate long bones of the toe.
  14. Distal Phalanges – long bones that make up the tip of the toe

Differences in Male and Female Pelvic Regions

  1. Female Ilium - wider
  2. Female Pubic Arch - larger
  3. Female Bone Thickness - thinner
  4. Female Sacrum - shorter

Upper Extremities

Structure, function and location (include projections and processes)

  1. Clavicle – collar bone
  2. Scapula – shoulder blade
  3. Glenoid fossa – scapula/humerus articulation socket
  4. Humerus – arm bone
  5. Radius–lateral bone of the forearm, on the thumb side.
  6. Ulna – medial bone of the forearm, on the pinky side. Forms the elbow with the humerus.
  7. Carpals – short bones of the wrist (8)
  8. Metacarpals – bones of the palm, numbered 1-5 from thumb to pinky
  9. Proximal Phalanges – long bones closest to palm
  10. Medial Phalanges – intermediate long bones of the fingers
  11. Distal Phalanges – long bones that form the finger tips.

Vertebrae and Bony Thorax

Structure, function and location (include projections and processes)

  1. Cervical Vertebrae (C1-C7)
  2. Atlas – holds the head, allows for nodding
  3. Axis – allows for lateral rotation
  4. Thoracic Vertebrae – (T1-T12) form the shoulders to the bottom of the ribs
  5. Lumbar Vertebrae – (L1-L5) forms the lower back, thicker and stronger than other vertebrae.
  6. Sacrum – 5 fused vertebral bones. Forms the posterior of the pelvis. The spinal cord ends here.
  7. Coccyx – 4 fused vertebral bones. The terminal of the spine. “tailbone”

Curvatures of the Spine

  1. Primary – Posterior curvature, Thoracic and sacral
  2. Secondary – anterior curvature, cervical and lumbar
  3. Kyphosis – hunch back, posterior curvature of the thoracic vertebrae
  4. Lordosis – sway back, anterior curvature of the lumbar vertebrae
  5. Scoliosis – lateral pulling on the vertebral column.