week 4 Flashcards
what is the anatomical position
standing straight, upper limbs by the sides with palms facing anteriorly, lower limbs together with toes facing anteriorly, head and eyes facing forwards.
what are the three cardinal planes and axes of the body?
coronal (anterior and posterior), sagital (medial and lateral), and transverse (superior and inferior).
what are flexion and extension?
flexion is bending, decreasing the angle between bones or moving a limb anteriorly. Extension is straightening, increasing the angle between bones or moving a limb posteriorly.
what is abduction and adduction?
abduction is moving away from the midline. adduction is moving towards the midline.
what is elevation and depression?
elevation is movement in a superior direction whilst depression is movement in an inferior direction.
what is protrusion and retrusion?
protrusion is movement anteriorly. retrusion is movement posteriorly.
what is protraction and retraction?
protraction is anterolateral movement of the scapula. retraction is posterolateral movement of the scapula.
what is pronation and supination?
pronation is rotation of radius medially so the palm faces posteriorly from anatomical position. supination is rotating the radius laterally so the palm faces anteriorly from anatomical position.
what is dorsiflexion and plantarflexion?
dorsiflexion is flexing the ankle joint, lifting the front of the foot and toes off the ground. Plantarflexion is bending the foot and toes towards the ground.
what is eversion and inversion?
eversion is movement of the sole of the foot away from the midline. inversion is movement of the sole of the foot towards the midline.
what are the properties of muscular tissue?
they respond to stimuli to produce action potentials, they contract when stimulated, they stretch without being damaged and can return to original length and shape after contraction and extension.
what is the structure of skeletal muscle?
epimysium, muscle, perimysium, fascicle, endomysium, muscle fibre.
what are circular fascicles?
circular fascicles are arranged into concentric rings. they surround external body openings. an example is the orbicularis oris.
what are convergent fascicles?
convergent fascicles are triangular or fan shaped and converge towards a single tendon of insertion. an example is the pectoralis major.
what are parallel fascicles?
the length of the muscle runs parallel to the long axis of the muscle. an example is the biceps brachii or the sartorius.
what are pennate fascicles?
pennate fascicles are short and attach obliquely. unipennate fascicles insert onto one side of the tendon, bipennate fascicles insert onto the tendon from opposite sides and multipennate fasicles insert onto the tendon from many directions.
what are tendons?
fibrous tissue linking a muscle belly to attachment site at bone.
what is raphe?
a line of ribrous tissue where one muscle joins to another.
what is an isometric contraction, concentric contraction and eccentric contraction?
an isometric contraction refers to a muscle contracting but not shortening (plank). a concentric contraction refers to a muscle contracting and shortening (bicep curl). an eccentric contraction refers to a muscle relaxing and extending (lowering barbell from bicep curl).
what is a prime mover, synergist, antagonist and fixator?
a prime mover is the muscle primarily responsible for producing the movement and the synergist is a muscle which assists the prime mover. the antagonist is the muscle which opposes the action of the prime mover. the fixator is a muscle which steadies the proximal part of the limb and helps move the distal part or the limb.
describe how the action of a muscle can be inferred by the position of the muscle relative to the joint it crosses.
a muscle that crosses on the anterior side of a joint produces flexion. a muscle that crosses on the posterior side of a joint produces extension. a muscle that crosses on the lateral side of a joint produces abduction. a muscle that crosses on the medial side of a joint produces adduction.
what is the function of osteoblasts and osteoclasts?
osteoblasts synthesise and secrete collage fibres to build bone. osteoclasts release lysosomal enzymes and acids to digest bone.
what are the processes of bone formation (ossification)?
all bones are derived from mesenchyme (embryonic connective tissue).
- intramembranous ossification: mesenchyme forms during embryonic period, and directly becomes bone.
- endochondral ossification: mesenchyme becomes cartliage during feotal period, and bone eventually replaces cartliage. the epiphyseal plate begins as cartliage and ossified once bone length is achieved .
How is longitudinal bone growth achieved?
involved two events:
1. interstitial growth of cartilage (chondrocytes) on the epiphyseal side of the epiphyseal plate.
2. replacement of cartliage on the diaphyseal side with bone via endochondral ossification.
the thickness of the epiphyseal plate remains constant, but bone on diaphyseal side increases in length.
