A&P test 5

Inserts on trapezium & base of 1st metacarpal, abducts & extends thumb

abductor pollicis longus

a neurotransmitter released at motor end plates by the axon terminals

acetylcholine

Destroys acetylcholine

acetylcholinesterase

the head of cross bridges interact with the active sites on _______________

actin

Origins on coracoid process, supraglenoid cavity, inserts on radial tuberosity

biceps brachii

the principle flexors of the forearm are the

biceps brachii and brachialis

Two "headed" muscle, inserts on head of fibula & lateral tibial condyle, flexes leg, extends thigh

biceps femoris

what does oxygen debt represent

difference between the amount of oxygen needed for aerobic muscle activity and the amount actually used

in what order would a scalpel first penetrate the layers of connective tissue upon cutting into the biceps brachii muscle

epimysium, perimysium, endomysium

Lack of acetylcholinesterase in the synaptic cleft would result in

excessive, continuous stimulation of the muscle fiber

Inserts on base of metacarpal II, extends and abducts hand

extensor carpi radialis longus

Inserts at base of 5th metacarpal, extends & adducts hand

extensor carpi ulnaris

Origin on lateral condyle of tibia, fibula & interosseous membrane, inserts on toes 2-5, prime mover of toe extension

extensor digitorum longus

Inserts on and extends distal phalanx of thumb

extensor pollicis longus

Origin on the borders of lower eight ribs (5-12), inserts on linea alba iliac and pubic crest, compresses abdomen, twisting at waist

external oblique

T/F A motor neuron and all the muscle cells that it stimulates are referred to as a motor end plate

false

T/F: all skeletal muscles have their origins and insertions on bone

false

T/F: an adductor muscle moves a body part away from the midline

false

T/F: four layers of muscle form the lateral abdominal wall

false

T/F: one motor unit innervates only one skeletal muscle fiber

false

T/F: the sternocleidomastoid muscle turns the head from side to side and extends the neck

false

T/F: the term biceps and triceps are used to indicate the number of insertions of a muscle

false

Inserts at base of metacarpal II and III, acts to flex and abduct hand

flexor carpi radialis

Origin on medial epicondyle of humerus, olecranon & posterior ulna, flexes & adducts hand

flexor carpi ulnaris

origin in posterior tibia, Flexes toes

flexor digitorum longus

Inserts on and flexes distal phalanx of thumb

flexor pollicis longus

Origin on epicranial aponeurosis, inserts on skin of eyebrows, raises eyebrows

frontal belly of the epicranius

Superficial leg muscle, inserts on posterior calcaneus by calcaneal tendon, plantar flexes foot

gastrocnemius

Forms bulk of the buttocks mass

gluteus maximus

the outer membrane around the muscle cell is called the ________, while the tunnel-like in-folding of the outer membrane are _________

sarcolemma; transverse tubules

Inserts on medial surface of proximal tibia, flexes, abducts and rotates hip laterally, produces cross-legged position

sartorius

which are the three hamstring muscles

semitendinosus, semimembranosus, biceps femoris

origin on nearly all ribs, rotates scapula laterally & upward as in pushing or punching

serratus anterior

diffusion across the cell membrane results in depolarization of the sarcolemma

sodium-potassium ions

Origin on superior tibia, fibula & interosseous membrane, involved in plantar flexion only

soleus

Origin on manubrium of sternum and clavicle, inserts on mastoid process of temporal bone

sternocleidomastoid

myoglobin _______

stores oxygen in muscle cells

creatine phosphate functions in the muscle cell by

storing energy that will be transferred to ADP to remake ATP

Origin on styloid process of temporal bone, retracts tongue

styloglossus

Origin on subscapular fossa of scapula, inserts on lesser tubercle of humerus

subscapularis

Turns the forearm and hand to anatomical position

supinator

Origin on supraspinous fossa of scapula; inserts on greater tubercle of humerus

suprespinatus

Origin on temporal fossa of cranium; elevates & retracts mandible

temporalis

Origin on iliac crest & superior iliac spine, inserts on iliotibial tract

tensor fasciae lata

which of the following supports the sliding filament theory of muscle contraction

the distance between the Z lines decreases during contraction

a general rule about the difference between an origin and insertion is

the insertion moves while the origin remains stationary

In examining a sarcomere, which of the following statements is correct?

the z lines establish the boundaries of the sarcomere

Prime mover of dorsiflexion of foot

tibialis anterior

Origin on superior tibia, fibula, and interosseous membrane, inserts on tarsal and metatarsal bones, prime mover of foot inversion, plantar flexes foot

tibialis posterior

the function of the transverse tubules in muscle contraction is to

transmit the action potential deep into the muscle cells

origin on iliac crest, inguinal ligament, lumbar fascia costal cartilage of 7-12, inserts on linea alba, pubic crest

transversus abdominis

Origin on occipital bone, C7-T12, inserts along acromion, spine of scapula & lateral clavicle

trapezius

3 origins, Inserts on olecranon of ulna, extends elbow

triceps brachii

Composed of gastrocnemius and soleus

triceps surae

when calcium binds to the muscle fibers

tropomyosin moves off the actin molecules

What is the role of tropomyosin in skeletal muscles?

tropomyosin serves as a contraction inhibitor by blocking the myosin binding sites on the actin molecules

when a skeletal muscle is stimulated to contract, Ca++ binds to

troponin

T/F: A resting potential is caused by a difference in the concentration of certain ions inside and outside the cell.

true

T/F: The effect of a neurotransmitter on the muscle cell membrane is to temporarily modify its ion permeability

true

T/F: the pectoralis major muscle is an antagonist to the latissimus dorsi muscle

true

the muscle that generates the most force in a given joint movement is called a/an

prime mover

turns the forearm and hand posteriorly

pronator quadratus

which of the following muscles originate on the humerus

pronator teres, brachialis, flexor carpi ulnaris, extensor carpis ulnaris

Origin on T12-L5, inserts on lesser trochanter of femur along with iliacus

psoas major

Inserts on patella & by patellar ligament on tibial tuberosity, extends leg

quadriceps femoris

origin on pubic symphysis inserts on xiphoid process, costal cartilage of ribs 5-7

rectus abdominis

Muscles comprising the quadriceps group include the

rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis

the skeletal muscle, light bands are called _______ and they contain _______

I bands; actin

the prime mover of inspiration is the

diaphragm

the sarcoplasmic reticulum stores _______ ions

calcium

Activate synaptic vesicles in axon terminals

calcium ions

Serves as the actual "trigger" for muscle contraction by removing the inhibition of the troponin molecules.

calcium ions

in an isotonic contraction, the muscle

changes in length and moves the "load"

Origin on arch of frontal bone; draws eyebrows medially & downward

corrugator supercilii

Used to convert ADP to ATP by transfer of a high-energy phosphate group. A reserve high-energy compound.

creatine phosphate

the rotator cuff muscles associated with the support of the shoulder joint consist of all the following muscles except

deltoid

Along with gluteus minimus, origin is on lateral surface of ilium; insertion on greater trochanter of femur

gluteus medius

Origin on inferior ramus of pubis & ischium, inserts below medial condyle of tibia

gracilis

Origin on body & greater horn of hyoid bone, depresses tongue

hyoglossus

Origin on iliac crest & iliac fossa, inserts on lesser trochanter of femur

iliacus

Origin on infraspinous fossa of scapula, inserts on greater tubercle of humerus

infraspinatus

Origin on iliac crest, lumbar fascia, inguinal ligament, inserts on linea alba, ribs 10-12, pubic crest

internal oblique

During vigorous exercise, there may be insufficient oxygen available to completely break down pyruvic acid for energy. As a result, the pyruvic acid is converted to ________.

lactic acid

Origin on lower thoracic & lumbar vertebrae, lower 3-4 ribs, iliac crest & lumbodorsal fascia, inserts on intertubercular sulcus of humerus

latissimus dorsi

Origin on transverse process of C1-C4, elevates/adducts scapula

levator scapulae

Origin on zygomatic arch, inserts on mandibular angle & ramus, closes jaw

masseter

in general where do the flexors of the wrist originate

medical epicondyle of the humerus

which of the following is the correct sequence of events for muscle contraction

motor neuron action potential, neurotransmitter release, muscle cell action potential, release of calcium ions from SR, ATP-driven power stroke, sliding of myofilaments

the head of the cross bridges formed during contraction Is located on the

myosin filaments

The sites where the motor nerve impulse is transmitted from the nerve endings to the skeletal muscle cell membranes are the

neuromuscular junctions

Origin on trapezius, lateral 1/3rd of clavicle, acromion, & scapular spine, inserts on deltoid tuberosity of humerus

none of these

the pronator teres and pronator quadratus

none of these

Origin on occipital bone and temporal bones, pulls scalp posteriorly

occipital belly of epicranius

Origin on frontal bone and maxillae, insert on eyelids, closes eyes

orbicularis oculi

Closes & protrudes lips as in kissing

orbicularis oris

Surface muscle on anterior chest, flexes, adducts and rotates arm medially

pectoralis major

if the calcaneal (Achilles) tendon was cut, which muscle action would be affected the most

planter flexion

Origin on fascia of deltoid & pectoralis major, inserts on mandible

platysma

Origin on lateral condyle of femur & meniscus of knee, inserts on proximal posterior tibia

popliteus

Origin on zygomatic bone, inserts on skin & muscle at corner of mouth, smile

zygomaticus major