lab quiz

Question 1

epicranus frontal belly

Answer 1

with aponeurosis fixed , frontal belly raises eyebrows

Question 2

orbicularis oris

Answer 2

various parts can be activated individually, closes eyes produces blinking, squinting and draws eyebrows inferiorly

Question 3

orbicularis oculi

Answer 3

draws eyebrows medially and inferiorly wrinkles skin of forehead

Question 4

zygomatics major

Answer 4

rasies raises lateral corners of the mouth upwards

Question 5

risorius

Answer 5

draws corner of lip laterally tenses lip,

Question 6

mentalis

Answer 6

protrudes lower lip

Question 7

buccinator

Answer 7

draws corner of mouth laterally, compresses cheek, holds food between teeth during chewing

Question 8

temporalis

Answer 8

closes jaw, elevates and retracts mandible

Question 9

masseter

Answer 9

prime mover of jaw closure

Question 10

strenocleidomastodi

Answer 10

loacted deep to platysa on anterolateral surface neck, fleshy parts on either side indicate limits of anterior and posterior triangles on the neck.

origin: manubrium of sternum and medial portion of clavicle.
insertion: mastoid process of temporal bone and superior nuchal line of occipital bone
action: simultaneous contraction of both muscle of pair cuases flexion of neck forward, acting independently

Question 11

Trapezius

Answer 11

location: most superficial muscle of posterior thorax, very broad orgin and insertion,
origin: occipital bone, ligamentum nuchae, spines of C7 and all thoracic vertebrae
insertion: acromion and spinous process of scapula, third of clavicle
action: extends head rasis,rotates and retracts scapula and stabilizes it

Question 12

latissimus dorsi

Answer 12

location: broad flat muscle of lower back extensive superficial organ
orgin: indirect attachment to spinous processes of lower six thoracic vertebrae, lumber vertebrae last three to four ribs and iliac crest
insertion: floor of intertubercular sulcus of humerus
action: prime mover of arm extension adducts and medially rotates arm, brings arm down in power stroke as in striking a blow

Question 13

rhombodis major+minor

Answer 13

location: beneath trapezius and inferior to levator scapulae rhomboid minor is the more superior muscle
origin: spinous processes of C7 and T1-T5
insertion: medial border of scapula
action: pull scapula medially, stabilize scapula, rotate glenoid cavity downward

Question 14

Levator scapulae

Answer 14

located at and side of neck deep to trapezius, origin transverse process of c1-c4
insertion: medial border of scapula superior to spine, action:elevate and adduct scapula with fixed scapula laterally flexes neck to the same side

Question 15

diaphragm

Answer 15

location: broad muscle forms floor of thoracic cavity dome shaped in relaxed state fiber converge from margins of thoracic cage toward a central tendon,
origin: inferior border of rib sternum, costal catilages of last six ribs and lumbar verebrae
insertion: central tendon,
action: prime mover of inspiration flattens on contraction, increasing vertical dimensions of thorax increases intra abdominal pressure.

Question 16

pectoralis major

Answer 16

location: large fan shaped muscle covering upper portion of chest ,
origin: clavicle sternum, cartilage of ribs 1-6 and aponeurosis of external oblique muscle
insertion: fibers converge to insert by short tendon into intertubercular sulcus of humerus
action: prime mover of arm flexion, adducts medially rotates arm with arm fixed pulls chest upward in forced inspiration

Question 17

serratus anterior

Answer 17

location: fan shaped muscle deep to scapula beneath and inferior to pectoral muscle on lateral rib cage,
orgin: later aspect os ribs 1-8
insertion: vertbral order of anterior surface of scapula
action: acting as a whole prime mover of arm abduction when only specific fibers are active can aid in flexion extension, and rotation of humerus

Question 18

deltoid

Answer 18

location fleshy triangular muscle forming shoulder muscle mass: intramuscular injection site
origin lateral 1/3 of clavicle acrominon and spine of scapula
insertion: deltoid tuberosity of humerus
action: acting as a whole, prime mover of arm abduction when only specific fibers are active can aid in flexion extension and rotation of humerus

Question 19

supraspinates

Answer 19

rotator cuff: location: obsucred by trapezius a rotator cuff muscle

origin: supraspinous fossa of scapula
insertion: greater tubercle of humerus
action: initaiates abduction of humerus stabilizes shoulder joint

Question 20

infraspinatus

Answer 20

rotator cuff muscle location: partially covered by deltoid and trapezius

orgin: infraspinous fossa of scapula
insertion: greater tubercle of humerus
action: lateral rotation of humerus, helps hold head of humerus in glenoid cavity

Question 21

teres minor

Answer 21

rotator cuff: location small muscle inferior to infraspinatus,

orgin: lateral margin of scapula
insertion: greater tubercle of humerus
action: as for infraspinatus

Question 22

triceps brachii

Answer 22

location: sole large fleshy muscle of posterior humerus three headed origin,
origin: long head inferior margin of glenoid cavity lateral head posterior humerus medial head distal radial groove on posterior humerus
insertion: olecranon of ulna
action: powerful forearm extensor, antagonist of forarm flexors and biceps.

Question 23

bicepes brachii

Answer 23

location: most familiar muscle of anterior humerus because this two headed muscle bulges when forearm is flexed
orgin: short head coracoid process long head supraglenoid turbercle and lip of glenoid cavity tendon of long head runs in intertubecular sulcus and within capsule of shoulder joint
insertion: radial tuberosity
action: flexion of elbow and supination of forearm