The Skeletal System

Question 1

Osteon

Answer 1

Functional unit of COMPACT bone

Question 2

Osteocyte

Answer 2

Help regulate the balance of new bone formation and old bone degeneration, regulates calcium balance

Question 3

Osteoblast

Answer 3

Build new bone, form new bones and add growth to existing bone tissue

Question 4

Osteoclast

Answer 4

Collapse bone, dissolve old and damaged bone tissue so it can be replaced by new healthier cells created by osteoblasts

Question 5

Lamellae

Answer 5

The ECM (extracellular matrix) around bone cells that gives compact bone its hardness and rigidity

Question 6

Lacunae

Answer 6

Gaps or open spaces that house bone cells

Question 7

5 Categories of Bone

Answer 7

Long
Short
Flat
Irregular
Sesamoid (round)

Question 8

Long Bone

Answer 8

Cylindrical shape, longer than it is wide, found in arms, legs, fingers and toes, function as levers and move when muscles contract

Question 9

Short Bone

Answer 9

cube-like shape, found in carpals (wrist) and tarsals (ankle), provide stability, support and limited motion

Question 10

Flat Bone

Answer 10

Thin, could be curved, serve as points of attachment for muscles and protect internal organs, Examples: skull, ribs, sternum (chest bone) and scapulae (shoulder blade)

Question 11

Irregular Bone

Answer 11

Not easily characterized by shape, does not fit into other categories, Examples: vertebrae and facial bones

Question 12

Sesamoid (round) Bone

Answer 12

a small round bone (shaped like a sesame seed) form in tendons and protect them from compressive forces, vary in number and placement from person to person, found in tendons associated with feet, hands, and knees

Question 13

Spongy Bone

Answer 13

Porous bone, found in the end of long bones, honeycomb shape

Question 14

Trabeculae

Answer 14

Small, needle like projections of bone that comprise spongy bone

Question 15

Compact Bone

Answer 15

The dense, hard outer layer of bone, provides strength and protection

Question 16

Periosteum

Answer 16

Outermost layer of bone, contains nerves and blood vessels, provides oxygenated blood to bone and allows for feeling within the bone

Question 17

Yellow Bone Marrow

Answer 17

Stores fat and stem cells that preserve fat for energy production, develop bone, cartilage, muscles and fat cells, located within bone

Question 18

Red Bond Marrow

Answer 18

Generates red blood cells, white blood cells, and platelets, located within bone

Question 19

Bone Marrow

Answer 19

Soft fatty tissue inside bone cavities, forms platelets, red and white blood cells, in the center of most bones and in the ends of spongy bones

Question 20

Axial Skeleton

Answer 20

Bones that form the body’s central axis, examples: head, neck, chest, back

Question 21

Appendicular Skeleton

Answer 21

Bones that attach (append) to your axial skeleton, examples: pelvis and limbs (arms, hands, feet, legs)

Question 22

Facial bones

Answer 22

Underlie the facial structure, form nasal cavity and enclose the eyeballs, support teeth of upper and lower jaw

Question 23

Brain case

Answer 23

The part of the skull that surrounds and protects the brain and houses ear structures

Question 24

Cranium (skull)

Answer 24

Composed of 22 bones including facial bones and brain case, supports the face and protects the brain

Question 25

Articulation

Answer 25

A joint, any place where adjacent bones or a bone and cartilage come together to form a connection

Question 26

Synarthrosis

Answer 26

immobile or nearly immobile joint, strong union between bones, provide protection for internal organs
syn= with/together arthourn= to fasted by a joint

Question 27

Diarthrosis

Answer 27

A freely movable joint, most body movements, mostly found in appendicular skeleton
di= 2 arthroun= to fasten by a joint

Question 28

Amphiarthrosis

Answer 28

A joint that has limited mobility
Amphi= both arthroun= to fasten by a joint

Question 29

Uniaxial

Answer 29

Movement in one anatomical plane
Example: elbow, knee

Question 30

Biaxial

Answer 30

Movement in two anatomical planes
Example: metacarpophalangeal joint (knuckle) of the hand

Question 31

Convex

Answer 31

Surface that is rounded or curved outward

Question 32

Concave

Answer 32

Surface that curves inward

Question 33

Antagonistic Muscle Pairs

Answer 33

Muscle pairs that contract and relax opposite one another, enables smooth and controlled movement
Example: bicep and tricep, hamstring and quadriceps

Question 34

Fibrous Joint

Answer 34

Bones are connected by fibrous connective tissue, synarthrosis

Question 35

Cartilaginous Joint

Answer 35

Bones are joined by hyaline cartilage or fibrocartilage, amphiarthrosis

Question 36

Synovial Joint

Answer 36

The articulating surfaces of the bones are not fully connected, but rather come into contact with each other within a joint cavity filled with lubricating fluid, diarthrosis
Most common joint in the body

Question 37

Multiaxial

Answer 37

Movement in all three anatomical planes
Example: shoulder and hip

Question 38

Pivot Joint

Answer 38

Rounded portion of bone is enclosed within a ring formed partially by bone and partially by ligament, bone rotates within this ring, uniaxial diarthrosis joint

Question 39

Hinge Joint

Answer 39

The round (convex) end of a bone fits into the end of a curved (concave) bone, uniaxial joint
Example: elbow, ankle, knee

Question 40

Condyloid Joint

Answer 40

A shallow groove at the end of one bone fits into a rounded part of an adjacent bone, biaxial joint
Example: bending and spreading of the fingers

Question 41

Saddle Joint

Answer 41

Both of the articulating surfaces for the bones have a saddle shape, fit together like a rider on a saddle, biaxial joint
Example: carpal and metacarpal at the base of the thumb

Question 42

Plane Joint

Answer 42

AKA gliding joint, the articulating surfaces are flat(ish) and slide against each other, multiaxial joint
Example: carpals and tarsals, clavicle and scapula

Question 43

Ball and Socket Joint

Answer 43

Rounded head of one bone fits into the concave articulation of another bone
multiaxial joint with the greatest range of motion