Week 2 Introduction to bones, joints and muscles

Question 1

functions of skeletal system

Answer 1

• protection
• support
• movement
• blood cell production
• calcium reserve

Question 2

bone cells

Answer 2

osteoblasts - form new bones
osteoclasts - dissolved old and damaged bones

Question 3

extracellular matrix

Answer 3

ground substance and collagen
–> compressive and tensile strength
–> 2/3 calcium salts, 1/3 collagen

Question 4

compact bone

Answer 4

hard, outer cell

Question 5

spongy bone

Answer 5

• inner trabeculae - compression and tensile
• medullary cavity

Question 6

periosteum

Answer 6

• lines compact bone except joint surfaces
• outer (fibrous) layer
• inner (osteogenic) layer

Question 7

bone marrow

Answer 7

red and yellow marrow

red - blood cell production
yellow - fat

Question 8

types of bones

Answer 8

long – femur
flat
irregular – coccyx
short – tarsal, carpal
pneumatic 空氣 – skull, cranium, rib bones
sesamoid – patella
accessory

Question 9

bone surfaces

Answer 9

articular (smooth)
non-articular

Question 10

bony markings

Answer 10

elevation
facet
depression
hole

Question 11

cartilage

Answer 11

• resilient 彈性, semi-rigid connective tissue

1. fibrocartilage – found in joints
2. elastic cartilage – found in ears, airway
3. hyaline cartilage – found in nose, trachea; no blood and nerve supply

Question 12

ossification processes

Answer 12

intramembranous - from fibrous tissue precursor
intracartilaginous - from hyaline cartilage model

Question 13

primary vs secondary centres of ossification

Answer 13

primary
- in the middle of each cartilage
- appeared at birth

secondary
- at the end of the cartilage model for long bones
- appear after birth

Question 14

parts of a developing bone

Answer 14

• diaphysis (from primary ossification centre)
• metaphysis (flared end of the diaphysis)
• epiphysis (from secondary ossification centre)

Question 15

epiphysial (growth) plate 骨骺（生長）板

Answer 15

• plate of hyaline cartilage
• primary cartilaginous joint
• disappears when epiphysis fuses with metaphysis (no more capacity for growth)

Question 16

epiphyses

Answer 16

• at the ends of developing long bones and produce growth
• pressure and traction epiphyses
• epiphyseal line = scar after cessation of growth

Question 17

type of joints

Answer 17

1. fibrous joints - suture, syndesmosis, gomophosis
2. cartilaginous joints - primary and secondary cartilaginous
3. synovial joints

Question 18

six typical characteristics of synovial joint

Answer 18

synovial fluid
synovial membrane
articular cartilage
ligaments
joint cavity
fibrous capsule

Question 19

types of synovial joints

Answer 19

uniaxial - pivot, hinge
biaxial - condyloid, saddle
multiaxial - ball and socket, plane

Question 20

special joint structures

Answer 20

labrum
disc
menisci
intracapsular tendons
bursae
fat pads

Question 21

fascial arrangement

Answer 21

fascial septa - perpendicular to skin (eg: intermuscular septa)
fascial sheets - parallel to skin
fascial sheaths - cylindrical, surround glands, nerves and vessels

Question 22

features of muscle fibres from skeletal muscle?

Answer 22

• has peripherally placed nuclei
• can be voluntarily controlled
• has fibres that function as a collective unit
• appears to have striations microscopically

Question 23

3 types of muscle

Answer 23

skeletal muscle -
stimulation: voluntary
type of activity: produce movement
appearance: large and very long cells

cardiac muscle - muscle of the heart
involuntary
acts to pump blood from the heart
connected end to end by complex junctions

smooth muscle - wall of hollow viscera and blood vessels
involuntary
acts mainly to propel substances and to restrict flow
spindle-shaped fibers without striations