The Musculoskeletal system

Question 1

Bones

Answer 1

Form body’s internal framework (skeleton)

Question 2

Functions of bones

Answer 2

Support - provide framework
Protection - bones surround tissue and organs
Storage of mineral and triglycerides - helps maintain homeostasis, blood calcium levels, bone marrow
Blood cell production - RBC, WHB, Platelets
Movement - bones act as levers to move body parts

Question 3

Bone structure

Answer 3

Connective tissue - osseous tissue, adipose tissue, cartilage
Nervous tissue - sensory neurons
Muscle and epithelial tissue - blood

Question 4

Compact bone

Answer 4

Arranged in osteons
Outer connective tissue - periosteum, blood vessels and nerves
Internal connective tissue - endosteum
diaphysis (shaft)

Question 5

Types of fracture
Comminuted fracture
Greenstick fracture
Compression fracture
Epiphyseal fracture
Depressed fracture
Avulsion fracture
Spiral fracture
Potts fracture
Pathological fracture
Transverse fracture bone
Colles fracture
Scaphoid fracture

Answer 5

Comminuted fracture - 3 or more pieces
Greenstick fracture - bone bends and cracks
Compression fracture - crushed
Epiphyseal fracture - bone breaks along epiphyseal
Depressed fracture - bone pressed inward
Avulsion fracture - tendon or ligament pulls of fragment of bone
Spiral fracture - ragged break from twisting forces
Potts fracture - break in tibia or fibula
Pathological fracture - disease that weakens bone
Transverse fracture bone completely breaks across diaphysis
Colles fracture - end of radius
Scaphoid fracture - common carpal bone fracture

Question 6

Articular capsule

Answer 6

Tough outer fibrous layer stabilise articulating bone
Inner synovial membrane - produces synovial fluid

Question 7

Bursa and tendon sheaths

Answer 7

Reduce friction

Question 8

Menisics - discs of cartilage

Answer 8

Stabilise joint
Reduce friction
Shock absorption

Question 9

Skeletal muscle layers

Answer 9

Bone
Tendon
Epimysium
Perimysium
Fascicle
Endomysium
Muscle fibre
Myofibrils
Sarcolemma

Question 10

Skeletal muscle contraction

Answer 10

1. AP travels along lower motor neuron and arrives at neuromuscular junction
2. Axon terminal release ACh, bind to chemically gated ion channels on the sarcolemma of a muscle
3. Chemically gated ion channels open and Na+ going to muscle fibre, depolarizes the sarcolemma and generates GP. GP stimulates AP
4. AP travels down sarcolemma triggers release of Ca2
5. Ca2 bind to troponin and pulls tropomyosin away from the actin active sites
6. Myosin heads bind to actin sites, pull thin myofilaments towards the M- line and then detach and repeat.
7. Each sarcolemma shorterns, each myofibril shortens, skeletal muscle shortens