Musculoskeletal System

Question 1

tendons, cartilage, ligaments

Answer 1

connects muscle to bone, connective tissue, bone connection and stability

Question 2

axial/appendicular skeleton

Answer 2

skull, vertebrae, thoracic cage

upper/lower limbs

Question 3

flat, long, sesamoid, short, irregular

Answer 3

protect organs, muscle attachment
levers
protect tendons
stability, limited motion
ligament attachment

Question 4

long bone anatomy

Answer 4

diaphysis (shaft)
metaphysics (spongy join)
epiphysis (spongy ends)
red bone marrow (blood cell production)
yellow bone marrow (lipid storage)
articulate cartilage (protect bone ends)
periosteum (outside of bone)
endosteum (medullary cavity)

Question 5

bone cells

Answer 5

osteogenic cells - produce osteoblasts
osteoblasts - build in/organic components
osteoclasts - break down bone
osteocytes - maintain matrix

Question 6

spongy vs compact bone

Answer 6

both ideal for weight bearing

spongy requires less ATP to move, resists force from different angles (endosteum-cased lamallae struts with canaliculi openings)

compact resists compression (arranged in parallel osteon, found in diaphysis and epithets)

Question 7

structurally classified joints

Answer 7

fibrous - no joint cavity
bony - complete fusion of bones
cartilaginous - no joint cavity (cartilage connections)
synovial - joint cavity for articulation

Question 8

synovial joints

Answer 8

articular capsule - encloses cavity
synovial membrane - produces synovial fluid
articular cartilage - protects ends of bone
synovial fluid - lubrication, nutrients
ligaments - hold bones together
bursae - synovial fluid sacs

Question 9

functionally classified joints

Answer 9

synarthrosis - immovable
amphiathrosis - slightly moveable
diathrosis - freely moveable

Question 10

types of movement

Answer 10

extension/flexion - increase/decrease angle between bones

abduction/adduction - away/towards midline

circumduction - distal body part movement

rotation - bone revolves around axis

Question 11

five main functions of muscles

Answer 11

movement, stability, tissue support, substance storage, heat generation

Question 12

smooth muscle

Answer 12

walls of internal structures, involuntary, can divide and regenerate

Question 13

cardiac muscle

Answer 13

only in heart, involuntary, autorhythmic, cannot divide or regenerate

Question 14

skeletal muscle

Answer 14

most abundant, voluntary, only pulls bone, cannot divide but can repair

Question 15

skeletal muscle organisation

Answer 15

muscle (organ)
fascicle (muscle fibres)
fibre (myocytes)
myofibril (contractile fibres)
myofilaments (actin, myosin, titin)

Question 16

sarcolemma, sarcoplasm, transverse tubules, sarcoplasmic reticulum, sarcomere

Answer 16

cell membrane around myocyte
cytoplasm in muscle cells
conduct action potentials
store/release calcium
contraction site

Question 17

muscle contraction

Answer 17

myosin head is energised, calcium arrives in area
calcium binds to troponin and releases tropomyosin
myosin head forms cross bridge with actin
ADP+P is released and myosin pulls actin to centre (M line)
ATP attached to myosin, actin releases and exposes active sites
myosin reenergised, reconnects to actin, actin slides closer

Question 18

contraction summary

Answer 18

acetylcholine releases and binds to receptors (synaptic transmission)
action potential to t-tubule
sarcoplasmic reticulum releases calcium
active site exposed, connections formed
contraction cycle begins
acetylcholine esterase breaks down ACh
sarcoplasmic reticulum recaptures calcium
contraction ends
relaxation (passive return to rest)

Question 19

hypertonia, hypotonia, hypertrophy, hyperplasia, atrophy

Answer 19

stiff, trouble moving, spasms
floppy, trouble standing, instability
increased use and growth
increased number of cells
decreased use and size