Musculoskeletal System L1

Question 1

How many bones does the adult skeleton consist of?

Answer 1

206

Cranial: 8
Auditory ossicles: 6
Facial: 14
Vertebral column: 26
Hyoid, sternum + ribs: 26
Upper limb: 64
Lower limb: 62

Question 1

Diagram L1

Answer 1

Coronal Suture
Sagittal suture

Question 2

State the functions of bone

Answer 2

1. Support -provide a rigid framework, allow us to stand, sit, move
2. Protection - enclose vital structures + viscera.
3. Movement / Leverage - anchoring attatchments (points) for muscles, allowing muscles to attach to bone. When muscles contract, they pull on bone attacthments, causing movement at joints, therefore, bones act as LEVERS, with joints as pivot points
4. STORAGE OF MINERALS - in bone matrix, primarily calcium + phosphorus
5. BLOOD CELL FORMATION
   (Haemopoiesis)
   in red marrow, not all bones have red marrow!
6. Lipid storage in emergencies - in yellow marrow (not in all bones)
7. Inorganic minerals (calcium, phosphorus): give bones hardness, resist compression
8. Organic collagens give bones flexibility, resist tension, pulling

Question 3

State the function of inorganic minerals in human bone

Answer 3

Calcium, phosphorus
Gives bone hardness allowing them to resist compression

Question 4

State the function of organic collagens in human bone

Answer 4

Gives bone flexibility
Resists tension / pulling

Question 5

Give an example of an inorganic mineral found in human bone

Answer 5

Calcium hydroxyapatite crystals (GIVE STRENGTH)

Question 6

Give an example of an organic collagen found in human bone

Answer 6

Type 1 collagen - provides flexivibility and resistance to stress

Question 7

Divisions and Classifications

Answer 7

The human body is BILATERALLY SYMMETRICAL

REFER TO DIAGRAM L1

Axial Bones: Mainly protective
- Skull
- Vertebral Column
- Ribs
- Sternum
- Hyoid

Appendicualr bones: To provide motility
- EVERYTHING ELSE

Question 8

State examples of appendicular bones

Answer 8

Upper limb bones:
- Humerus (upper arm bone connecting the shoulder to elbow

Question 9

Describe the classication of bones

Answer 9

Shape of bones relate to function

5 major shapes:

1. Long - HUMERUS
2. Short (cuboidal) - CARPAL
3. Flat - PARIETAL
4. Irregular - VERTEBRA
5. Sesamoid - PATELLA
6. SUTURAL BONES (do we need to know?) - irregular, found in sutures of cranial bones, not found in all indivduals

REFER TO DIAGRAM L1

Question 10

Describe the structure and function of the axial skeleton

Answer 10

Bones lined up vertically along an axis. This is FOR SUPPORT

Skull, vertebral (spinal) column, hyoid, ribs, sternum

Skull: encases brain
Vertebral column: Encases spinal cord
Ribs: Cage around the heart and lungs

Question 11

Describe the structure and function of the appendicular skeleton

Answer 11

Bones include those of upper limbs and lower limbs

Includes girdles (skeletal components/ bony structures that connect appendicular skeleton (upper limbs + lower limbs) to axial skeleton

Two sets of girdles

Include SCAPULAE (shoulder blades) + PELVIS (HIP GIRDLE) linking structures between limbs and axial skeleton

Pelvis - connects bones of lower limbs (legs) to axial skeleton

Question 12

What are the surface markings on bones?

Answer 12

Specific features / irregularities on surface of bones - found where there is connective tissue attached to bone including

• Fascia - fibrous connective tissue
• Ligaments - connect bone to bone
• Tendons - connect muscle to bone
• Aponeuroses - sheet like connective tissue

Question 13

State the surface marking on bones

Answer 13

DIAGRAM L1

Head
Neck
Tubercle
Intertrochanteric line
Lesser trochanter
Attachment site for gluteus minimus
Greater trochanter

Question 14

What is a joint?

Answer 14

The site where 2 or more skeletal elements come together / articulate

Question 15

Describe the classification of joints

Answer 15

Grouped into types according to

1. Structure
2. Movements (or lack of movement) they exhibit