Week 3 - Skeletal system

Question 1

What is Bone made up of?

Answer 1

Bone is connective tissue.
Composition of the bone matrix is called osteoid.
- collagen

Question 2

What is collagen?

Answer 2

produced by osteoblasts
* gives bone tensile strength by resisting stretching
* contributes to bone flexibility

Question 3

Functions of Bones

Answer 3

1. support of the body
2. protection of soft organs
3. movement due to attached skeletal muscles
4. storage of minerals and fats
5. blood cell formation

Question 4

Compact Bone

Answer 4

1. forms outer, hard shell of the bone
2. provides solid attachments for muscles, tendons, ligaments
3. organised into osteons

Question 5

Spongy Bone

Answer 5

1. porous lattice of rods and plates called trabeculae
2. sponge like appearance; spaces are filled with red bone marrow and blood vessels
3. imparts strength without adding too much weight

Question 6

Structure of a long bone

Answer 6

1. diaphysis (shaft)
2. epiphyses
3. periosteum
4. endosteum
5. articular cartilage

Question 7

Diaphysis (shaft)

Answer 7

• compact bone collar surrounds medullary (marrow) cavity
• medullary cavity in adults contains fat (yellow marrow)

Question 8

Epiphyses

Answer 8

1. expanded ends
2. spongy bone interior
3. epiphyseal plate
4. articular cartilage on joint surfaces

Question 9

The periosteum

Answer 9

1. outer fibrous layer
2. inner osteogenic layer
3. contains osteoblasts and osteoclasts

Question 10

Endosteum

Answer 10

1. delicate membrane on internal surfaces of bone
2. also contains osteoblasts and osteoclasts

Question 11

Articular cartilage

Answer 11

1. covers the external surfacce of the epiphyses
2. made of hyaline cartilage
3. decreases friction at joint surfaces

Question 12

Role of vitamin D

Answer 12

• Vitamin D is essential for maintenance of bone mineralisation through regulation of calcium and phosphorus homeostasis
• vitamin D is important for normal bone development and maintenance

Question 13

microscopic anatomy of bone

Answer 13

1. osteon
2. central canal
3. perforating canal

Question 14

**Developmental aspects of the skeletal system **

Answer 14

• at birth, the skull bones are incomplete
• bones are joined by fibrous membranes - fontanelles
• fontanelles are completely replaced with bone within 2 years after birth

Question 15

The pectoral girdle (shoulder)

Answer 15

composed of 2 bones
1. clavicle - collarbone
2. scapula - shoulder blade
allow the upper limb to have free movement

Question 16

Hand Bones

Answer 16

• carpals - wrist
• metacarpals - palm
• phalanges - fingers

Question 17

functions of Joints

Answer 17

• hold bones together
• allow for mobility

Question 18

**classification of joints **

Answer 18

• fibrous joints - genrally immovable
• cartilaginous joints - immovable or slightly moveable
• synovial joints - freely moveable

Question 19

types of synovial joints

Answer 19

1. ball and socket
2. pivot
3. saddle
4. hinge
5. gliding
6. condylar

Question 20

inflammatory conditions associated with joints

Answer 20

1. osteoarthritis
2. rheumatoid arthritis
3. gouty arthritis

Question 21

Osteoarthritis

Answer 21

• most common chronic arthritis
• probably related to normal aging processes

Question 22

Rheumatoid Arthritis

Answer 22

• an autoimmune disease - the immmune system attacks joints
• symptoms begin with bilateral imflammation of certain joints

Question 23

gouty arthritis

Answer 23

• inflammation of joints is caused by a deposition of urate crystals from the blood
• can usually be controlled with diet