A&PL: Quiz 5

-partially covered by deltoid and trapezius; a rotator cuff muscle -O: infraspinous fossa of scapula -I: greater tubercle of humerus -lateral rotation of humerus

*infraspinatus* -comments -Origin -Insertion -action

-medial superficial muscle, extends from pubis to rib cage; ensheathed by aponeuroses of oblique muscles; segmented -O: pubic crest and symphysis -I: xiphoid process and costal cartilages of ribs 5-7 -*flexes and rotates vertebral column*; increases abdominal pressure; fixes and depresses ribs; stabilizes pelvis during walking; used in sit-ups and curls

*rectus abdominis* -comments -origin -insertion -action

muscles that oppose or reverse a movement *can be prime movers in their own right... example: biceps (prime mover of elbow flexion) is antagonized by the triceps (prime mover of elbow extension)

antagonists

A. Serratus anterior B. Transversus abdominis C. Internal oblique D. External oblique E. Aponeurosis of the external oblique F. Pectoralis major G. Linea alba H. Tendinous intersection I. Rectus abdominis J. Inguinal ligament (formed by free inferior border of the external oblique aponeurosis)

anterior view of the muscles forming the anterolateral abdominal wall

prime mover

biceps brachii during elbow flexion

serratus anterior

fan shaped muscle

*aka fixation muscles* specialized synergists immobilize the origin of a prime mover so that all the tension is exerted at the insertion (i.e. muscles that help maintain posture)

fixators

prime mover

gluteus maximus during hip extension

pectoralis minor

identify the agonist that moves forward/rotates scapula:

antagonist

iliopsoas during hip extension

rectus abdominis

medial, superficial, segmented abdominal muscle

a. circular b. convergent c. parallel d. unipennate e. multipennate f. fusiform g. bipennate

patterns of fascicle arrangements in muscles

flexor carpi radialis

powerful flexor of wrist; abducts hand

*aka agonists* muscles that are responsible for producing a particular movement

prime movers

aid the action of agonists either by assisting with the same movement or by reducing undesirable or unnecessary movement *contraction of a muscle crossing 2+ joints would cause movement at all joints spanned if the synergists weren't there to stabilize them

synergists

-elbow flexion -olecranon process of ulna

the brachialis is a synergist of what action?

antagonist

triceps brachii during elbow flexion

external intercostals, internal intercostals, and diaphragm

what are the muscles of respiration?

rotator cuff muscles

what group of muscles O on scapula I on humerus and stabilize glenohumeral joint

to become familiar with PowerLab system: the PowerLab hardware and the Chart software

what is the purpose of this PowerLab experiment?

the fibers of the antagonist are stretched and in the relaxed state *can also regulate prime mover by providing some resistance, to prevent overshoot or to stop its action

when a prime mover is active...

palmar longus -flexion

which muscle attaches to palmar aponeurosis?does it aid in flexion or extension?

-SIT: Supraspinatus; Infraspinatus; Teres minor -All have their origins on the scapula, and they all insert onto the humerus -help to stabilize glenohumeral joint; produce external and internal rotation at the shoulder

Rotator cuff muscles: -which muscles make up rotator cuff? -where do they O and I? -what is the rotator cuff's function?

flex trunk on thigh; flex thigh; lateral flexion of vertebral column

Iliopsoas: how does it relate to hip flexion?

synergist

describes relation of brachialis to biceps brachii in elbow flexion

*1. direction of muscle fibers* -a muscle with fibers/fascicles running parallel to imaginary line = rectus -muscle fibers run at right angles = transverse =muscle fibers run obliquely = oblique *example: the rectus abdominis is the straight muscle of the abdomen* *2. relative size of the muscle* -maximus (largest) -minimus (smallest) -longus (long) -brevis (short) *example: gluteus maximus* *3. location of the muscle* -named for the bone with which they are associated *example: temporalis muscle covers temporal bone* *4. number of origins* -bicep = 2 origins; tricep = 3; etc. *ex: quadriceps* *5. location of muscles origin and insertion* *-ex: sternocleidomastoid* has origins on sternum (sterno) and clavicle (cleido) and inserts on mastoid process *6. shape of muscle* -deltoid=triangle; trapezius=trapezoid *ex: trapezius* *7. action of muscle -adductor muscles of inner thigh bring about adduction *ex: extensor muscles in the wrist*

muscles are named on the basis of the following criteria:

*A. Trapezius* B. Deltoid C. Rhomboid major *D. Latissimus dorsi* *E. Levator scapulae* F. Rhomboid minor G. Supraspinatus H. Infraspinatus I. Teres minor J. Teres major

muscles of the neck, shoulder, and thorax (posterior)

a. pectorals major b. biceps brachii c. pectoralis minor d. serratus anterior

muscles of the thorax and shoulder acting on the scapula and arm