Chapter 7 - Skeletal System

Question 1

Functions of the skeletal system

Answer 1

Support, protection, movement, storage, hematopoiesis

Question 2

Calcitonin

Answer 2

Thyroid gland hormone that increases mineralization of calcium and reduces blood calcium

Question 3

Parathyroid hormone

Answer 3

Parathyroid hormone that decreases calcium in the bone and increases blood calcium

Question 4

Hematopoiesis

Answer 4

Blood cell formation. Carried out in red bone marrow

Question 5

Four major types of bones

Answer 5

Long, short, flat, irregular

Question 6

Diaphysis

Answer 6

Shaft of a long bone. Hollow, hard, compact

Question 7

Medullary cavity

Answer 7

Hollow area of the long bone. Contains yellow bone marrow

Question 8

Epiphyses

Answer 8

End of the long bone. Contains red bone marrow

Question 9

Articular cartilage

Answer 9

Thin layer of cartilage that covers the epiphysis. Small cushion

Question 10

Periosteum

Answer 10

Strong membrane of dense fiber covering a long bone except at joint surfaces

Question 11

Endosteum

Answer 11

Thin membrane that lines the medullary cavity

Question 12

Diploe

Answer 12

Cancellous bone layer of a flat bone

Question 13

Compact bone

Answer 13

Hard, dense outer layer of bone. Appears solid to the naked eye.

Question 14

Cancellous bone

Answer 14

Porous inside of bones. Also called spongy bone. Filled with red or yellow marrow

Question 15

Trabeculae

Answer 15

Lattice beams of the cancellous bone

Question 16

Osteon

Answer 16

Extra cellular matrix of compact bone. Composed of calcified matrix arranged in layers like an onion.

Question 17

Concentric lamella

Answer 17

Rings of the osteon

Question 18

Central canal

Answer 18

Inner portion of the concentric lamella. Contains blood vessels.

Question 19

Transverse canals

Answer 19

Connect central canals in compact bone

Question 20

Osteocytes

Answer 20

Mature bone cells. No longer active making osteoblasts. Contained in the lacunae

Question 21

Canaliculi

Answer 21

Connect lacunae with each other and with central canal of each osteon. Nutrients are passed through and distributed

Question 22

Cartilage

Answer 22

Flexible like firm plastic. Collagen fibers reinforce the matrix. No blood vessels so slow to repair after injury.

Question 23

Chondrocytes

Answer 23

Cartilage cells.

Question 24

Osteoblasts

Answer 24

Bone forming cells

Question 25

Osteoclasts

Answer 25

Bone reabsorbing cells

Question 26

Endochondral ossification

Answer 26

Process of cartilage turning to bone

Question 27

Epiphyseal plate

Answer 27

Area of cartilage between epiphyses and diaphysis. As long as this remains the bone continues to grow.

Question 28

Epiphseal line

Answer 28

Mark where centers of ossification have fused together. Bone growth ceases.

Question 29

Intramembranous ossification

Answer 29

Calcification of fibrous membranes of some bones like the skull

Question 30

Fontanels

Answer 30

Soft spots of a newborn baby’s skull

Question 31

Number of skull bones

Answer 31

28

Question 32

Number of cranium bones

Answer 32

8

Question 33

Number of facial bones

Answer 33

14

Question 34

Number of ear bones

Answer 34

6

Question 35

Sinuses

Answer 35

Cavities of the cranial bones. 4 pairs called paranasal sinuses when opening into the nose

Question 36

Sutures

Answer 36

Immovable joints

Question 37

Hyoid bone

Answer 37

Anchors the tongue and larynx. Not connected to any other bones.

Question 38

Number of bones in the spinal column

Answer 38

26 total bones. 24 vertebrae.

Question 39

3 kinds of joints

Answer 39

Synarthroses, amphiarthroses, diarthroses

Question 40

Synarthroses

Answer 40

No significant movement. Connective tissue holds them tightly together. Sutures

Question 41

Amphiarthroses

Answer 41

Slight movement possible at the joint. Usually made of cartilage. Pelvis, vertebrae.

Question 42

Diarthroses

Answer 42

Freely movable joints. Joint capsule, joint cavity, layer of cartilage.

Question 43

Joint capsule

Answer 43

Made of fibrous connective tissue and lined with synovial fluid. Fits over ends of two bones. Joins to shaft of the bones.

Question 44

Articular cartilage

Answer 44

Layer over the joint end of bones that absorbs shock. Smooth surface to lower friction.

Question 45

Joint cavity

Answer 45

Lined with synovial membranes that secrete synovial fluid.

Question 46

Functional types of diarthroses

Answer 46

Ball and socket, pivot, hinge, gliding, saddle, condyloid.