Skeletal System

Question 1

Components (4)

Answer 1

Bones
Cartilage
Tendons
Ligaments

Question 2

Functions (5)

Answer 2

Body Support 
Organ Protection
Body movement
Mineral Storage
Blood cell production

Question 3

Ligaments

Answer 3

The connective tissue that holds bones together

Question 4

Tendon

Answer 4

Strong bands of connective tissue that attach to bones

Question 5

What minerals are stored in the bones? (2)

Answer 5

Calcium and phosphorus

Question 6

What other tissue is stored in bone cavities?

Answer 6

Adipose - used as a source of energy if needed

Question 7

Types of cartilage (3)

Answer 7

Hylanine cartalige
fibrocartilage
elastic cartilage

Question 8

Hyaline Cartliage as related to. bone (2)

Answer 8

1. Most bones in body start out as hyaline cartilage model

2. Bone growth and repair begin with hyaline cartilage

Question 9

Chondroblasts

Answer 9

Immature hyaline cartilage cells

produce a matrix surrounding themselves

Question 10

Chondrocyte

Answer 10

Mature chondroblasts with a matrix around it

Question 11

Lacuna

Answer 11

The space occupied by a chondrocyte

Question 12

What makes up the chondrocyte matrix? (2)

Answer 12

Collagen - for strength

Proteoglycans - trap water to make cartilage resilient

Question 13

Perichondrium

Answer 13

• a protective connective tissue that covers cartilage

- Blood vessels and nerves penetrate the outer layer of the perichondrium but do not enter the cartilage matrix

Question 14

Cartilage gets nutrients by

Answer 14

Diffusion in cartilage matrix

Question 15

Layers of perichondrium

Answer 15

Outer - dense irregular connective tissue with fibroblasts

inner layer - delicate, fewer fibers, contains condroblasts

Question 16

Articular cartilage

Answer 16

Hyaline cartilage covers the ends of bones where they come together to form joints
Does not have perichondrium, blood, or nerves.

Question 17

Types of cartilage growth

Answer 17

appositional

interstitial

Question 18

Appositional growth

Answer 18

chondroblasts in perichondrium add new cartilage to the outside edge of existing cartilage

Question 19

Interstitial growth

Answer 19

chondrocytes in the center of tissue divide and add more matrix in-between existing cells

Question 20

Bone Matrix composition

Answer 20

35% organic - collagen and proteoglycans

65% inorganic material - calcium phosphate crystal hydroxyapatite

Question 21

Functional characteristics of bone (2)

as compared to reinforced concrete

Answer 21

Flexible strength - collagen (steel bars)

Weight-bearing strength - mineral components (concrete)

Question 22

Bone cells (3)

Answer 22

Osteoblasts
Osteocytes
Osteoclasts

Question 23

Osteoblasts

What they do, what differentiates them, and what 2 things do they produce?

Answer 23

Bone-forming
Extensive endoplasmic reticulum; numerous ribosomes
Produce collagen and proteoglycans
Derived from osteochondral progenitor cells

Question 24

Matrix vesicles

Answer 24

Released by Osteoblasts

high concentrations of Ca2+ and Po43-

Question 25

Ossification | What is it & how does it grow?

Answer 25

formation of new bone by osteoblasts | Appositional growth

Question 26

Osteocytes

Answer 26

An osteoblast that has secreted enough bone matrix to become surrounded by it Relatively inactive Retain connection to other osteocytes through cell extensions Derived from osteoblasts

Question 27

Lacunae

Answer 27

Spaces without matrix but occupied by osteocyte

Question 28

Canaliculi

Answer 28

Spaces occupied by osteocyte cell extension

Question 29

Osteoclasts

Answer 29

Bone-destroying cells Reabsorb (breakdown) bone to get Ca2+ and phosphate ions (send the Ca2+ back to the blood) Multi-nucleated Derived form stem cells in red bone marrows

Question 30

Ruffled border

Answer 30

Highly folded, differentiated cell membrane of the osteoclast

Question 31

Osteogenesis imperfecta

Answer 31

Brittle Bone disorder | Mutations the make defective type I collagen

Question 32

Type 1 OI

Answer 32

Type 1 OI > mild, most common. Caused by too little formation of normal type 1 collagen - predisposed to fracture, spinal curvature, loose joins, brittle teeth, hearing loss, blue tint to the white of eyes

Question 33

Type 2 OI

Answer 33

Most severe Lethal within the first week of life BReathing failure due to rib fractures

Question 34

Type 3 OI

Answer 34

Bones that fracture easily, before and during birth

Question 35

Osteochondral progenitor cells

Answer 35

Stem cells that can become osteoblasts or chondroblasts | Located in the inner layer of the perichondrium

Question 36

When does ossification occur?

Answer 36

In a fetus When growing When repairing a fracture

Question 37

Woven bone

Answer 37

The first type of bone formed Weak Collagen fibers randomly oriented in many directions

Question 38

Lamellar bone

Answer 38

Mature bone | Collagen fibers lie parallel to one another

Question 39

Lamellae

Answer 39

Layers of lamellar bone

Question 40

Spongy bone

Answer 40

Appears porous, has less bone matrix, and more space

Question 41

Compact bone

Answer 41

more bone matrix and less space

Question 42

Trabeculae

Answer 42

Interconnecting rodes/ plate of the bone in spongy bone Between the rods are bone marrow and blood vessels No blood vessels penetrate trabeculae, so osteocytes must get nutrients through canaliculi

Question 43

Osteon

Answer 43

The functional unit of a long bone, compact bone | Made of concentric rings of matrix

Question 44

Central canal

Answer 44

Center of the "target" of the osteon | Where blood vessels enter the bone

Question 45

Concentric lamellae

Answer 45

circular layers of bone matrix that surround central canal

Question 46

Circumferential lamellae

Answer 46

Thin plates that extend around the bone

Question 47

Interstitial lamellae

Answer 47

Between osteons | Remnants of concentric or circumferential lamellae that were removed during bone remodeling