The Skeletal system

Question 1

What are the organic components of osseous tissue matrices?

Answer 1

Water (25%), extracellular fibres (25%), inorganic salts (50%)

Question 2

Where does bone get it’s durability?

Answer 2

The deposition of calcium salts in the matrix

Question 3

How many bones does an adult human contain?

Answer 3

206

Question 4

What are the main functions of bone?

Answer 4

Protection
Movement
Support

Bone marrow
Storage

Question 5

What are the 5 classifications of bone shape?

Answer 5

Short, long, flat, irregular, sesamoid

Question 6

What are long bones specially used for?

Answer 6

Lever action in conjunction with muscles

Question 7

What are short bones specially used for?

Answer 7

Areas where limited movement is required

Question 8

What are flat bones especially used for?

Answer 8

Protection of soft tissues and providing large attachment sites for muscles

Question 9

What are sesamoid bones especially for?

Answer 9

Areas where there is considerable tension or stress, they protect tendons from excessive wear and tear

Question 10

What is component X?

Answer 10

Diaphysis

Question 11

What are the components X?

Answer 11

Metaphysis

Question 12

What are components X?

Answer 12

Epiphysis (Proximal/distal)

Question 13

What are components X?

Answer 13

Articular cartilage

Question 14

What is component A?

Answer 14

Spongy/cancellous bone

Question 15

What is component B?

Answer 15

Epiphyseal line (Growth plate)

Question 16

What is component C?

Answer 16

Red bone marrow

Question 17

What is component D?

Answer 17

Endosteum

Question 18

What is component E?

Answer 18

Compact/cortical bone

Question 19

What is yellow bone marrow mostly made of?

Answer 19

Fat

Question 20

What does red bone marrow produce?

Answer 20

Red blood cells

Question 21

How does the epiphyseal plate change with growth?

Answer 21

It starts as a layer of hyaline cartilage which allows the bone to grow in length. After adulthood when growth stops this layer is changed to bone

Question 22

What is the periosteum and it’s functions?

Answer 22

A layer covering the outside of the bone that isolates the bone from surrounding tissues and plays a role in the growth and repair of bones

Question 23

What is the endosteum?

Answer 23

The inner surface of bone

Question 24

When is the endosteum active?

Answer 24

During growth of the bone

Question 25

What is the diaphysis?

Answer 25

The long tubular mid section of long bones

Question 26

What is the medullary cavity?

Answer 26

The hollow centre of the bone containing yellow bone marrow

Question 27

What are epiphyses?

Answer 27

The expanded ends of long bone

Question 28

What is the metaphysis?

Answer 28

An area in a mature long bone where the epiphysis joins the diaphysis

Question 29

What does the periosteum consist of?

Answer 29

An outer fibrous layer and an inner osteogenic layer

Question 30

What forms the outer layer of all bones?

Answer 30

Compact/cortical bone

Question 31

What gives compact/cortical bone its definitive hardness and strength?

Answer 31

It has a strong calcified bony matrix, filled with organic ground substance leaving only tiny spaces inbetween. Theses small spaces contain the osteocytes and are connected to each other by tiny channels called canaliculi.

Question 32

What are the tiny gaps in compact bone that contain osteocytes?

Answer 32

Lacunae

Question 33

What percentage of the human skeleton is compact/cortical bone?

Answer 33

80%

Question 34

How is compact/cortical bone structured?

Answer 34

Many cylindrical units called osteons surrounded by interstitial lamallae and outer circumferential lamallae

Question 35

What is the structure of an osteon?

Answer 35

Concentric layers called lamellae around a longitudinal central (Haversian) canal containing blood vessels, nerves and lymphatic vessels. Perforating (Volkmann's) canals branch off of the central canal at right angles spreading vessels and nerves outward and inward

Question 36

What is the structure of spongy/cancellous bone?

Answer 36

Lamellae arranged in needle-like threads of bones called trabeculae which contain osteocytes in lacunae. The spaces in between these trabeculae are filled with bone marrow.

Question 37

What is the upper arm bone?

Answer 37

Humerus

Question 38

What are the lower arm bones?

Answer 38

Ulna and radius

Question 39

What is the thicker of the lower arm bones?

Answer 39

Radius

Question 40

What bones form the heel of your hand?

Answer 40

Carpals

Question 41

What bones form the palms of the hands?

Answer 41

Metacarpals

Question 42

What bones form the fingers?

Answer 42

Phalanges

Question 43

What is the upper leg bone?

Answer 43

Femur

Question 44

What is the knee capbone called?

Answer 44

Patella

Question 45

What are the lower leg bones?

Answer 45

Tibia and fibia

Question 46

What is the larger of the lower leg bones?

Answer 46

Tibia

Question 47

What is the shoulder blade bone called?

Answer 47

Scapula

Question 48

What is the collar bone called?

Answer 48

Clavicle

Question 49

What is the ankle bone called?

Answer 49

Talus

Question 50

What is the heel bone?

Answer 50

Calcaneus

Question 51

What bones form the midfoot and hind foot?

Answer 51

Metatarsals and tarsals

Question 52

What bones form the forefoot?

Answer 52

Metatarsals and phalanges

Question 53

What are the two divisions of the skeleton?

Answer 53

Axial skeleton and appendicular skeleton

Question 54

What does the axial skeleton consist of?

Answer 54

The head and trunk of the body including the skull, hyoid bone, chest and spine

Question 55

What are the main bones of the skull?

Answer 55

Frontal Nasal Zygomatic Maxilla Mandible Sphenoid Parietal Temporal Occupital

Question 56

What are the 5 sections of the spine and how many vertebrae are in each?

Answer 56

Cervical (7) Thoracic (12) Lumbar (5) Sacral (5) Coccyx (Fused section)

Question 57

What is the function of bone marrow?

Answer 57

Red bone marrow helps produce blood cells (RBC, leukocytes and platelets). Yellow bone marrow helps store fat. (Yellow bone marrow also contains mesenchymal stem cells. These are cells that can develop into bone, fat, cartilage, or muscle cells.)

Question 58

Do adult bones contain mostly red or yellow bone marrow, why?

Answer 58

Most bones in an adult body contain yellow bone marrow because yellow bone marrow starts to replace red bone marrow over time.

Question 59

Which two minerals make up the majority of bone structure?

Answer 59

Calcium carbonates Calcium phosphates

Question 60

What is ossification?

Answer 60

Bone formation

Question 61

What is the basic process of intramembranous ossification?

Answer 61

Mesodermal cells are transformed into osteoblasts which secrete osteoid which becomes calcified

Question 62

What is the basic process of endochondral ossification?

Answer 62

Mesodermal cells differentiate into cartilage cells, the bones are initially formed from this

Question 63

What is the 'Growth plate'?

Answer 63

During ossification there is actively growing cartilage between the shaft of a long bone & the epiphysis this is called the epiphyseal plate or 'growth plate'.

Question 64

For how long into life are bones developing?

Answer 64

Bones continue to grow in length and thickness into adolescence.

Question 65

What is non-traumatic bone remodelling and what is required for it?

Answer 65

Bones constantly repairing themselves. - Under normal daily stresses bones develop micro fractures and are repaired. Vit D, calcium, phosphate, parathyroid hormone & various steroid hormones are required for this to continue.