Musculo Skeletal System Flashcards
Division of the skeleton
axial skeleton - skull, spinal column, sacrum, ribs, sternum
appendicular skeleton - clavicle, scapula, humerus, ulna, radius, carpals, metacarpals, phalanges, pelvis, femur, patella, fibular, tarsals, metatarsals, phalanges
Microscopic bone structure
compact/dense bone
spongy bone
epiphysis
bone matrix
Compact bone
hard outer shell - makes up the diaphysis
spongy bone
a mixture of small bone pieces and red bone marrow
yellow bone marrow
found in the centre of the diaphysis - stores fat
Epipysis
shaft of the bone
epipyseal line - site of growth
bone matrix
non cellular material that separates connective tissue
contains inorganic salts increasing strength and rigidty
joints
any site at which 2 or more bones join together, may or may not permit movement
classified according to structure or function
Fuction of the skeleton
shape and support, movement, storage of minerals and fats, protection of vital organs, blood cell production
Fixed joints
Permits little or no movement
eg. sutures in the skull
Cartilaginous joints
slight movement in all directions
eg. humerus and scapular, femur and pelvis
Synovial joints
ball and socket joints hinge joints pivot joints gliding joints saddle joints ellipsoid joints
Ball and socket joints
Rotary motion in all directions
eg. scapular, femur, and pelvis
Hinge joints
movement in one direction only
eg. elbow
Pivot joints
rotating
eg. axis and atlas
Gliding joints
side to side, back and forth
eg. sternum and clavicle, scapula and clavicle
Saddle joints
small movements: side to side, back and forth
eg. thumb and metacarpals
Ellipsoid joints
up and down, side to side
eg. radius and carpals, metacarpals and phalanges,
Synovial structures
fibrous capsule, synovial membrane, synovial fluid, articular cartilage, bursae, accessory ligaments
Fibrous capsule
consists of dense, fibrous connective tissue connected to the periostem of the articulating bones, flexibility allows movement, strength stops dislocation,
Structure that holds bones together
Synovial membrane
makes up the inner layer of the capsule
loose connective tissue, well supplied with capillaries
Lines the entire joint; except articular cartilage and disc
Synovial fluid
lubricates and provides nourishment for cells, reduces friction
Consists of phagocytes; clears debris
Secreted by synovial membrane
Articular cartilage
not in every joint
directs synovial to areas that require it
Bursae
sacks of synovial fluid, prevents friction between a bone and ligament, tendon or skin
Accessory ligament
holds bones together
Joint movement
Adduction - away from the midline
Abduction - towards the midline
Extension - increasing the inner angle of the joint
Flexion - decreasing the inner angle between articulating joints
Cartilage
Type of connective tissue that acts as structural support
Nutrition by diffusion from perichondrium
Muscles
Made up of contractile tissue; has the capacity to contract and extend, return to original length after stretching
- contractibility
- extensibility
- elasticity
types of muscle
- skeletal (straited)
- Involuntary (smooth)
- cardiac
Muscle control
can be conscious or unconscious
impulses are delivered through neurons
Either reduce the distance between body parts, or decrease the amount of space they surround
Muscle structure
muscle fibres contains parallel myofibrils, made up of myofilaments (actin, myosin)
Muscle contraction - actin and myosin slide past one another
Sacromere
a compete straited unit
Skeletal muscle
Attached to bones by tendons, pull bones together
Antagonist pairs
perform opposing actions
Agonist; desired movement
Antagonist; opposing action
eg. bicep contracts (agonist), triceps relax (antagonist)
Origin and insertion
Muscle origin; end attached to stationary bone
muscle insertion; end attached to moving bone
