The Skeletal System

Question 1

What are the four parts of the skeletal system?

Answer 1

1) Bones
2) Joints
3) Cartilages
4) Ligaments

Question 2

What are the two divisions of the skeletal system?

Answer 2

Axial and Appendicular

Question 3

What are the five functions of the bones?

Answer 3

1) Support of the body
2) Protection of soft organs
3) Movement due to attached skeletal muscles
4) Storage of minerals and fats
5) Blood cell formation

Question 4

How many bones are in the adult skeleton?

Answer 4

206

Question 5

Two basic types of bone tissue?

Answer 5

1) Compact Bone (Homogeneous)

2) Spongy Bone (Small needle like pieces, open spaces)

Question 6

The different types of bones include?

Answer 6

1) Long Bones (ex: femur, humerus)
2) Short Bones (ex: carpals, tarsals, calcaneus)
3) Flat Bones (ex: skull, ribs, sternum)
4) Irregular Bones (ex: vertebrae, hip)

Question 7

Two parts of a long bone?

Answer 7

1) Diaphysis (shaft and composed of compact bone)

2) Epiphysis (ends of the bone and composed mostly of spongy bone)

Question 8

Structures of a long bone include?

Answer 8

1) Periosteum
2) Sharpey’s fibers
3) Arteries
4) Articular Cartilage
5) Medullary Cavity

Question 9

What is Periosteum?

Answer 9

• Outside covering of the diaphysis

- Fibrous connective tissue membrane

Question 10

What is Sharpey’s fibers?

Answer 10

Secure periosteum to underlying bone

Question 11

What do the Arteries do?

Answer 11

Supply bone cells with nutrients

Question 12

What is Articular cartilage?

Answer 12

• Covers the external surface of the epiphysis
• made of hyaline cartilage
• decreases friction at joint surfaces

Question 13

What is the Medullary Cavity?

Answer 13

• Cavity of the shaft
• Contains yellow marrow (mostly fat) in adults
• Contains red marrow (for blood cell formation) in infants

Question 14

What are the microscopic parts of a bone?

Answer 14

1) Osteon (Haversian System)
2) Central (Haversian) Canal
3) Perforating (Volkman’s) Canal

Question 15

What is an Osteon (Haversian System)?

Answer 15

The unit of bone

Question 16

What is the Central (Haversian) Canal?

Answer 16

• Opening in the center of an osteon

- Carries blood vessels and nerves

Question 17

What is the Perforating (Volkman’s) Canal?

Answer 17

• Canal perpendicular to the central canal

- Carries blood vessels and nerves

Question 18

Layers of the osteon include?

Answer 18

1) Lacunae
2) Lamellae
3) Canaliculi

Question 19

What is Lacunae?

Answer 19

• Cavities containing bone cells (osteocytes)

- Arranged in concentric rings

Question 20

What is Lamellae?

Answer 20

• Rings around the central canal

- Sites of lacunae

Question 21

What is Canaliculi?

Answer 21

• Tiny Canals

- Radiate from the central canal to lacunae

Question 22

What is the skeleton primarily made up of in embryos?

Answer 22

Hyaline Cartilage

Question 23

What is much of the cartilage replaced by during development?

Answer 23

Bone

Question 24

Where does cartilage remain after growth?

Answer 24

1) Bridge of the nose
2) Parts of the ribs
3) Joints

Question 25

What allows for growth of the long bone during childhood?

Answer 25

Epiphyseal Plates

Question 26

What happens to cartilage in the bone during growth?

Answer 26

1) New cartilage is continuously formed 2) Older cartilage becomes ossified 3) Cartilage is broken down

Question 27

What are the three types of bone cells?

Answer 27

1) Osteocytes (mature bone cells) 2) Osteoblasts (bone-forming cells) 3) Osteoclasts (bone-destroying cells)

Question 28

What are the two main types of bone fractures?

Answer 28

1) Closed (simple) fracture - doesn't penetrate the skin | 2) Open (compound) fracture - penetrates through the skin

Question 29

What are the six types of bone fractures?

Answer 29

1) Communited - breaks into fragments 2) Compression - completely crushed 3) Depressed - pressed inward 4) Impacted - broken bone ends are forced into other bones 5) Spiral - ragged break from excessive twisting 6) Greenstick - breaks incompletely

Question 30

How are bone fractures treated?

Answer 30

Reduction and immobilization of the skin (realignment of the bone)

Question 31

What are the steps to repair bone fractures?

Answer 31

1) Hematoma (blood filled swelling) is formed 2) Break is splinted by frobrocartilage to form a callus 3) Fibrocartilage callus is replaced by a bony callus 4) Bony callus is remodeled to form a permanent patch

Question 32

What are the three main types of joints?

Answer 32

1) Fibrous Joints - generally immovable, united by fibrous tissue (ex. sutures) 2) Cartilaginous Joints - immovable or slightly movable, united by cartilage (ex. pubic symphysis, intervertbral joints) 3) Synovial Joints - freely movable, separated by a joint cavity, synovial fluid is found in the joint cavity

Question 33

What are the four features of synovial joints?

Answer 33

1) Articular cartilage (hyaline cartilage) covers the ends of bones 2) Joint surfaces are enclosed by a fibrous articular tissue 3) Have a joint cavity filled with a synovial fluid 4) Ligaments reinforce the joint

Question 34

What are the six types of synovial joints?

Answer 34

1) Pivot - ex) neck 2) Hinge - ex) elbow, knee 3) Saddle - ex) thumb 4) Ball & Socket - ex) hip, shoulder 5) Candyloid - ex) radius, carpals 6) Plane - ex) tarsals