Musculoskeketal 1

Question 1

What makes up the adult skeleton?

Answer 1

Axial

Appendicular

Question 2

How many bones in the axial skeleton?

Answer 2

80 (some pairs)

Question 3

How many bones in the appendicular skeleton?

Answer 3

126 (all paired)

Question 4

Function of axial skeleton?

Answer 4

Support/protection

Haemopoiesis (red bone marrow)

Question 5

Function of appendicular skeleton?

Answer 5

Movement 
Fat storage (yellow bone marrow)

Question 6

Two meanings of bone?

Answer 6

1. Bone the organ (organs made up of different types of tissues)
2. Bone the tissue (one of the tissues found in the bones of the skeleton)

Question 7

Function of the skeletal system?

Answer 7

1. Support
2. Protection
3. Movement
4. Calcium and phosphorous reserve
5. Haemopoiesis
6. Fat storage

Question 8

Thin inner fibro-cellular layer lining the medullary cavity?

Answer 8

Endosteum

Question 9

Inside of bone?

Answer 9

Medullary cavity

Question 10

Outer fibro-cellular sheath surrounding the bone?

Answer 10

Periosteum

Question 11

Parts of the extra cellular matrix?

Answer 11

Fibres (organic)
Ground substance (inorganic)

Question 12

What type of fibres are in extra cellular matrix?

Answer 12

Collagen fibres type I and V

Question 13

Purpose of fibres in ECM of bone?

Answer 13

To resist tension (stretching/pulling)

Question 14

What type of tissue is bone?

Answer 14

Specialised connective tissue

Question 15

What is the main component of ground substance?

Answer 15

Hydroxyapatite (Ca10(PO4)6OH2)

Question 16

Purpose of ground substance?

Answer 16

To resist compression (squeezing, crushing)

Question 17

Types of cells in bone?

Answer 17

Osteogenic
Osteoblasts
Osteocytes
Osteoclasts

Question 18

Purpose of cells in bone?

Answer 18

Cell reserve
Bone formation
Bone maintenance
Bone destruction

Question 19

What do the combination of fibre (tension) and ground substance (compression) result in?

Answer 19

Torsion

Question 20

What is the precursor to osteogenic cells?

Answer 20

Unspecialised stem cells (mesenchyme = embryonic CT)

Question 21

What are known as osteoprogenitor cells?

Answer 21

Osteogenic cells

Question 22

What is the location of osteogenic cells?

Answer 22

Surface of bone in the periosteum and endosteum. Also found inside canals of compact bone

Question 23

What is the function of the osteogenic cell?

Answer 23

They’re normally dormant but can divide and supply developing bone with bone-forming cells

Question 24

What is the precursor of an osteoblast?

Answer 24

Osteogenic cell

Question 25

Where is the location of the osteoblast?

Answer 25

Usually in a layer under the Peri or endosteum. Wherever new bone is being formed

Question 26

What is the function of the osteoblast?

Answer 26

Synthesis, deposition and mineralisation of osteoid

Question 27

What is osteoid?

Answer 27

The organic extra cellular matrix (mainly collagen) of bone, synthesised by osteoblasts prior to mineral deposition

Question 28

What is the composition of osteoid?

Answer 28

70% collagen, remainder is proteoglycans and other proteins

Question 29

What happens to the precursor osteoid matrix?

Answer 29

It's eventually infiltrated with bone salts (hydroxtlyapatite)

Question 30

What's the infiltration of the precursor osteoid matrix with bone salts called?

Answer 30

Calcification

Question 31

What does calcification do to osteoid?

Answer 31

It makes the bone strong but dense, thus nutritive fluids cannot diffuse freely through it

Question 32

What is the precursor to osteocyte?

Answer 32

Osteoblast

Question 33

Where is the osteocyte located?

Answer 33

Trapped within lacunae inside bone.

Question 34

How do osteocytes communicate with neighbouring cells?

Answer 34

Through their long cellular processes and canaliculi

Question 35

Function of osteocytes?

Answer 35

Bone tissue maintenance

Question 36

Precursor of osteoclasts?

Answer 36

Fusion of monocyte (white blood cell) progenitor cells (Syncytium)

Question 37

Location of osteoclasts?

Answer 37

At sites where bone resorption is occurring (wherever you want to get rid of bone)

Question 38

Function of osteoclasts?

Answer 38

Secretes acid and enzymes to dissolve the mineral and organic components of bone