Science 7.3-7.4

Question 1

longer than they are wide

Answer 1

long bones

Question 2

roughly cube shaped, nearly as wide as they are long

Answer 2

short bones

Question 3

which often have the job of protecting vital organs

Answer 3

flat bones

Question 4

Any bone that cannot be easily clas-sified into one of the first three categories is considered a

Answer 4

irregular bone

Question 5

The bone’s shaft

Answer 5

diaphysis

Question 6

each bulged end

Answer 6

epiphysis

Question 7

gives the bone great strength and rigidity

Answer 7

compact bone

Question 8

the dense compact bone is replaced by a lightweight, porous tissue called what

Answer 8

spongy bone

Question 9

special tissue that manufactures red blood cells and white blood cells for the body’s circulatory and immune systems

Answer 9

red marrow

Question 10

the core of the diaphysis is a hollow, cylindrical
cavity, like a tunnel running the length of the bone

Answer 10

medullary cavity

Question 11

the red marrow in the medullary cavity is replaced by a fatty substance called

Answer 11

yellow marrow

Question 12

The hardness of bone is caused by microscopic crystals of a mineral substance

Answer 12

hydroxyapatite

Question 13

a tough, resilient protein that serves the same purpose as the steel rods in reinforced concrete, helping to prevent the mineral crystals from being pulled away from each other

Answer 13

collagen

Question 14

special cells that constantly move through your bones, removing old materials to make room for new

Answer 14

Osteoclasts

Question 15

move into the Haversian canals behind the osteoclasts, constructing new collagen fibers and hydroxyapatite crystals as they go; blood vessels also enter the canals, supplying the osteoblasts with nutrients

Answer 15

osteoblasts

Question 16

, a disease in which the bones are weak and deformed

Answer 16

rickets

Question 17

bones adjust their shapes to the physical stress placed upon them.

Answer 17

wolff’s law

Question 18

cartilage forms were complete, osteoblasts began to move through them, replacing the soft, rubbery cartilage with collagen-reinforced hydroxyapatite

Answer 18

ossification

Question 19

A break or crack in a bone

Answer 19

fracture

Question 20

occurs when a bone breaks cleanly in two

Answer 20

transverse fracture

Question 21

the bone cracks and bends but remains held together by its collagen fibers

Answer 21

a greenstick fracture

Question 22

bone is twisted or exposed to sudden impact at either end

Answer 22

spiral fracture

Question 23

when part of a bone is broken into multiple fragments.

Answer 23

comminuted fracture

Question 24

occurs when a bone cracks or breaks but does not pierce through the skin

Answer 24

simple fracture

Question 25

occurs when the broken bone pierces through the skin

Answer 25

compound fracture

Question 26

places where bones join

Answer 26

joints

Question 27

they join the bones rigidly together

Answer 27

immovable joints

Question 28

they make some bending and twisting movements possible

Answer 28

slightly movable joints

Question 29

allow a wide range of motion

Answer 29

freely movable joints

Question 30

bones are held together by strong bands of fibrous connective tissue called what

Answer 30

ligaments

Question 31

fluid that lubricates joints

Answer 31

synovial fluid

Question 32

allows a bone to move back and forth in a single plane, like a door swinging on its hinges

Answer 32

hinge joints

Question 33

The most freely movable joints

Answer 33

ball-and-socket joints

Question 34

type of joint that allows only rotating movement

Answer 34

pivot joint

Question 35

in which one bone merely slides across the surface of another

Answer 35

gliding joint

Question 36

a saddle-shaped portion of one bone nestles into a saddle-shaped portion of another bone

Answer 36

saddle joint

Question 37

inflammation of the joints

Answer 37

arthiritus

Question 38

when the ligaments of a joint are overstressed

Answer 38

sprain

Question 39

a joint is overstressed to the extent that a bone pops out of alignment and must be relocated

Answer 39

dislocation

Question 40

primary function is to move the parts of the skeleton

Answer 40

skeletal muscles

Question 41

specialized for relatively slow, powerful, and prolonged contractions

Answer 41

smooth muscles