Musculoskeletal System 1 Flashcards
3 Components of the muscular system
Muscles
Tendons
Ligaments
Common prefix for components of the muscular system
My-, myo-, mus-, musculo-,
e.g. musculocutaneous nerve, myocardium
3 Components of the skeletal system
Bones, Cartilage, Joints
Common prefixes for components of the skeletal system
Os-, Osteo-, Oss-
e.g. Ossiculum, Ossification
Functions of the skeletal system
Support
Protection
Movement
Storage -> bones act as mineral stores for calcium and phosphorous
Haematopoeisis -> formation of blood cellular compartments
Classification of bones
Flat bone -> key for protection e.g skull
Long bone
Irregular bone
Short bone
Sesamoid -> (floating bone) e.g found within patella tendon
Anatomical sections of a long bone
Epiphysis
Metaphysis
Diaphysis
Key anatomical features of a long bone
Articular surface (articular cartilage)
Epiphyseal line
Spongy bone
Compact bone
Marrow/ medullary cavity
Periosteum
Bone marrow
What is the vertebral column
= the spine
What is the bony thorax?
= rib cage
What are girdles?
the point at which limbs attach e.g. shoulder girdle
Axial Skeleton
- Skull / cranium
- Vertebral column
- Bony thorax
Appendicular Skeleton
- Limbs (Appendages)
- Pectoral girdle
- Pelvic girdle
What are the 2 regions of the skull?
Skeleton of head and cranial vault - Neurocranium
Skeleton of face - Viscerocranium
Role of the skull
- Facilitates initial entry of food, oxygen etc into the body
- Supports organs of special senses
- Protects brain
Made up of may bones.
5 Regions of the Vertebral Column
Cervical - neck region
Thoracic - associated with ribs
Lumbar - spine / vertebra in lower back
Sacral- between last vertebra and hip bone
Coccygeal (caudalis) - bone structure at base of spine
Role of the bony thorax
- Muscle attachment
- Protect thoracic organs
- Respiration
Consists of ribs and sternum
Attached to thoracic vertebral column
Appendicular Skeleton Function
Main facilitator of movement
Extensive and significant adaptations
Basic arrangement is the same in all mammals
Pectoral girdle
Scapula - shoulder bone
Clavicle - collar bone
What are the similarities of bones in the upper and lower limbs in humans and quadrupeds:
At the top: 1 bone for proximal part
2 bones in forearm/leg
Numerous short bones with long bones for digits
How does skeletal homology form evidence of evolution
Form follows function
Stances:
- Planti grade
- Digiti grade
- Unguli grade
- stands on feet
- stands on toes
- stands on nails
Order of a muscle
Myofilaments –> Myofibril –> Muscle fibre / cell –> fascicle –> Muscle
Tendons Function
Connects muscle to bone
Rich in collagen
Can be cylindrical or flat
Muscle mass is normally proximal in the limb
Aponeurosis
Attaches muscle to bone / muscle
Flat sheet rather than round tendon
Ligaments function
Connect bone to bone
Stabilize joints
How do muscles move joints
Muscles contract by shortening. Muscles always pull - they never push.
For a muscle to move a joint, it needs to attach to a bone either side of it (needs to span it)
Some muscles only span one joint = Brachialis and Pectineus
Some muscles span multiple joints = Biceps brachii and sartorius
How do muscles work?
Muscles never work alone
When a prime mover contracts the antagonistic muscle / muscle group relaxes
An antagonist muscle contracts to oppose the action of a prime mover
Muscle contraction - Isontonic meaning
Change in length
No change in tension
Muscle contraction - Isontonic - Concentric meaning
Muscle shortens
Muscle contraction –> eccentric meaning
Muscle lengthens
Used against a force
Muscle contraction - Isometric meaning
Change in tension
No change in length
Types of muscle fibre - Fast twitch
Fast contractions
Quick to fatigue
e.g chickens - fast flight over short distance
Types of muscle fibre - Slow twitch
Slower contractions
Resistant to fatigue
e.g. ducks - slower flight over longer distances
What is muscle tone?
Where muscles are in a state of partial contraction
Joints
Cavitated
Synovial = freely moveable joints
Joints
Solid–> Fibrous
Gomphosis = Teeth
Syndesmosis = Tibiofibula
Suture = Skull
Joints
Solid –> Cartilaginous
Primary = synchondrosis, growth plates
Secondary = Symphysis, Pelvis
