Osteology

Question 1

What are the functions of bones other than structure

Answer 1

Support: for the internal framework that supports and anchors all soft organs.
Protection: bones protect soft body organs
Movement: skeletal muscles, attached to bones by tendons, use the bones as levers to move the body and its parts
Storage: Fat is stored in the internal cavities of the bones, the bones themselves store minerals (most important calcium and phosphorus)
Blood cell formation/hematopoiesis: occurs within the marrow cavities of certain bones

Question 2

What is the difference between the axial and appendicular skeleton

Answer 2

Axial: Bones that form the longitudinal axis :Head, trunk of vertebral column (ribcage, hyoid)
Appendicular: the bones of the limbs and girdles (scapula/clavicles)

Question 3

What are the two basic types of osseous or bone tissue

Answer 3

Compact Bone: is dense and looks smooth and homogenous.

Spongy Bone: is composed of small needle like pieces of bone and lots of open space

Question 4

What are the 4 classifications of bones and examples

Answer 4

Long bones: usually longer then they are wide. mostly compact bone. All bones of limbs.
Short bones: generally cube shaped and contain mostly spongy bone. bones of the knee or carpel bones and short bones
Flat bones: thin, flattened and usually curved. two thin layers of compact bone sandwiching a layer of spongy bone between them. Most bones of skull, ribs, and the sternum.
Irregular bones:bones that do not fit other categories. vertebrae and hip bones fall into this group.

Question 5

What are the 8 structures of the long bone

Answer 5

Diaphysis (shaft), Periosteum , Epiphysis (ends of long bone), Aritcular cartilage (glassy hyaline cartilage), Epiphyseal plate (in young growing bones), Epiphyseal line (remainder of plate found after done growing), Yellow marrow or medullary cavity (adipose tissue stored in shaft in adults), and red marrow (stored in shaft of young and infants)

Question 6

What is periosteum

Answer 6

fibrous connective tissue that covers and protects the diaphysis connected by perforated fibers

Question 7

What is the articular cartilage compared to periosteum

Answer 7

it covers the external surface instead of periosteum. It provides a smooth slippery surface that decreases friction at joint surfaces

Question 8

Explain the epiphyseal plate

Answer 8

epiphyseal plate cause the lengthwise growth of a long bone. By the end of puberty, when hormones inhibit long bone growth, epiphyseal plates have been completely replaced by bone

Question 9

What is the anatomical name for the shaft of a long bone? For its ends?

Answer 9

Diaphysis = shaft Epiphysis = ends

Question 10

What are osteocytes and where are they found

Answer 10

Osteocytes are mature bone cells found in the matrix in tiny cavities called lacunae

Question 11

lacunae are….

Answer 11

they are arranged in concentric circles called lamellae

Question 12

What is the importance of the canaliculi

Answer 12

they are tiny canals that radiate outward to all lacunae that forms a transportation system that connects all the bone cells to the nutrient supply through hard bone matrix

Question 13

What is the difference of the Osteon or haversian system to canaliculi

Answer 13

Canaliculi are tiny canals joining the lacunae where as the Osteon is the central canal in the matrix rings

Question 14

In an embryo, what do they have instead of long bones

Answer 14

Hyaline cartilage which is the model for bones

Question 15

How does the bone change from hyaline cartilage

Answer 15

Hyaline cartilage is covered with bone matrix by bone-forming cells called osteoblasts. When bone has formed, hyaline cartilage is digested leaving the medullary cavity

Question 16

Where is they hyaline cartilage still seen at birth

Answer 16

Articular cartilage at the end of long bones and epiphyseal plates

Question 17

what is the bone formation process called

Answer 17

Ossification

Question 18

How do osteoblasts become osteocytes

Answer 18

Osteoblasts lay down new matrix and become trapped within it. When they are trapped, they become osteocytes

Question 19

What is needed to absorb calcium in the bloodstream

Answer 19

Vitamin D

Question 20

Name the 8 bone fractures

Answer 20

Simple, compound, comminuted, compression, depressed, impacted, spiral, greenstick

Question 21

Explain the repair of bone fractures

Answer 21

• Hematoma is formed, bone cells deprived of nutrition die
• Break is splinted by fibrocartilage callus (new capillaries grow into clotted blood , disposal of dead tissue by phagocytes) callus contains many elements such as cartilage matrix, boney matrix and collagen fibers which act as a splint to the broken bone
• bony callus formed, osteoblasts and steoclasts migrate to area and multiply, fibrocartilage is gradually replaced by callus made of spongy bone
• next few months, bony callus is remodeled in response to mechanial stresses so that is forms a strong permanent patch at fracture site

Question 22

Name the 7 types of bone markings

Answer 22

Tuberosity, Crest, Trocahnter, Line, Tubercle, Epicondyle, Spine

Question 23

Name the 4 projections that help to form joints

Answer 23

Head (bony epansion carried on narrow neck)
Facet (Smooth nearly flat articular surface)
Condyle (Rounded articular projection)
Ramus (Arm like bar of bone)

Question 24

Another word for joint

Answer 24

articulations

Question 25

What are the 3 functional classes of joints and their meaning

Answer 25

Synarthrosis- immoveable
Amphiarthrosis- slightly movable
Diarthrosis- freely moving

Question 26

What are the 3 structural classifications of joints and explain

Answer 26

Fibrous- bones are united by fibrous tissue (sutures of the skull)
Cartilaginous- bone ends are connected by cartilage (amphiarthrotic-pubic symphysis of pelvis, intervertebral joints)
Synovial- articulating bone ends are separated by a joint cavity containing synovial fluid