Skeletal System

Question 1

What are the primary functions of the skeletal system?

Answer 1

Supports body, protects vital organs, allows movement, storage, hemopoiesis

Question 2

What is hemopoiesis?

Answer 2

Production of WBC and platelets in bone marrow

Question 3

What are the main components of the skeletal system?

Answer 3

• Bones
• Joints
• Cartilage

Question 4

How are bones classified by shape?

Answer 4

• Long
• Short
• Flat
• Sesamoid
• Pneumatic
• Irregular

Question 5

What defines long bones?

Answer 5

Greater in length than width; examples include humerus and femur

Question 6

What are short bones characterized by?

Answer 6

Cuboid, approx. equal in all directions; example: carpus

Question 7

Describe flat bones.

Answer 7

Thin and expanded in two directions; consist of two plates of compact bone separated by spongy bone; examples include scapula and ribs

Question 8

What are sesamoid bones?

Answer 8

Resemble sesame seeds; develop within a tendon; example: patella

Question 9

What are pneumatic bones?

Answer 9

Contain air spaces or sinuses that communicate with the atmosphere; examples: frontal and maxillary bones

Question 10

Define irregular bones.

Answer 10

Unpaired bones on median plane; offer protection, support, and muscular attachment; example: vertebrae

Question 11

What are the two parts of the skeleton?

Answer 11

• Axial skeleton
• Appendicular skeleton

Question 12

What is included in the axial skeleton?

Answer 12

• Skull
• Vertebral column
• Sternum
• Ribs

Question 13

What is the function of the vertebral column?

Answer 13

Supports head and body; protects spinal cord

Question 14

What are the regions of the vertebral column?

Answer 14

• Cervical
• Thoracic
• Lumbar
• Sacral
• Coccygeal

Question 15

What is the first vertebra called?

Answer 15

Atlas (C1)

Question 16

What is the second vertebra called?

Answer 16

Axis (C2)

Question 17

What is the typical number of cervical vertebrae in various animals?

Answer 17

7 in horses, cattle, pigs, sheep, and goats

Question 18

What are true ribs?

Answer 18

Ribs attached directly to the sternum by costal hyaline cartilage

Question 19

What are false ribs?

Answer 19

Ribs caudal to the true ribs

Question 20

What does the appendicular skeleton consist of?

Answer 20

• Thoracic limbs (shoulder, arm, forearm, carpus, metacarpus, phalanges)
• Pelvic limbs (pelvic girdle, thigh, crus, tarsus, metatarsus, phalanges)

Question 21

What is ossification?

Answer 21

Formation of bone by deposition of calcium salts in osteoid tissue

Question 22

What is compact bone?

Answer 22

Hard layer that covers most bones; gives strength and support

Question 23

What is cancellous bone?

Answer 23

Also called spongy bone; consists of trabeculae filled with red marrow

Question 24

What is the medullary cavity?

Answer 24

Innermost space of the shaft of the long bone; lined by endosteum

Question 25

What is the epiphysis in long bones?

Answer 25

Either end of a long bone; proximal epiphysis is closest to the body, distal epiphysis is farthest

Question 26

What is the diaphysis?

Answer 26

Cylindrical shaft of a long bone between the two epiphyses

Question 27

What is the metaphysis?

Answer 27

Flared area adjacent to the epiphysis; widest part of a long bone

Question 28

What is the epiphyseal cartilage?

Answer 28

Layer of hyaline cartilage that separates diaphysis and epiphysis; only area that can lengthen

Question 29

What is articular cartilage?

Answer 29

Thin layer of hyaline cartilage covering the articular surface of bone; reduces friction

Question 30

What are osteoblasts?

Answer 30

Bone forming cells that lay down bone matrix

Question 31

What are osteoclasts?

Answer 31

Bone destroying cells involved in bone remodeling and growth

Question 32

What are osteocytes?

Answer 32

Mature bone cells embedded in the bone matrix; direct other bone cells

Question 33

What is the process of growth in length of bones called?

Answer 33

Endochondral ossification

Question 34

What happens to cartilage as an animal ages?

Answer 34

Cartilage closest to diaphysis becomes mineralized and is replaced by bone

Question 35

What holds bones and muscles together?

Answer 35

* Ligaments (connect bone to bone) * Tendons (connect bone to muscle or muscle to muscle)

Question 36

What is a bursa?

Answer 36

Fluid filled sac that cushions between bones and tendons or muscles

Question 37

What are joints also called?

Answer 37

Articulations

Question 38

What are the three classifications of joints?

Answer 38

* Fibrous joints * Cartilaginous joints * Synovial joints

Question 39

What are fibrous joints?

Answer 39

Immovable joints united by dense fibrous tissue

Question 40

What are cartilaginous joints?

Answer 40

Slightly movable joints united by cartilage

Question 41

What are synovial joints?

Answer 41

Freely movable joints containing an articular cavity

Question 42

What is the function of synovial fluid?

Answer 42

Lubricates joints and acts as a shock absorber

Question 43

What is a ginglymus joint?

Answer 43

Hinge joint that moves only on one plane

Question 44

What is a trochoid joint?

Answer 44

Pivot joint that allows rotary movement around one axis

Question 45

What is a spheroid joint?

Answer 45

Ball and socket joint that permits movement in nearly any direction

Question 46

What is meniscus?

Answer 46

Curved fibrous cartilage in joints that acts as a cushion from force