Human Anatomy and Physiology Chapter 10
which of the following statements about muscles of the elbow joint is true
-The biceps brachii has two heads that share the same origin site -The brachioradialis originates and inserts on the ulna -The biceps brachii is posterior extensor - none of these statements are true ******
sequence of events at the neuromuscular junction
1. Ca2+ enters the axon terminal 2. Synaptic vesicles release ACh 3. ACh binds to ACh receptors. 4. Ligand-Gated cation channels open 5. Na+ enters K+ exits 6. Membrane potential is less negative.
Without lateral rotation of the humerus by the teres minor and infraspinatus muscles, the maximum angle of abduction would be _____________.
90 degrees
cross bridge cycle starts when
Ca2+ from the sarcoplasmic reticulum binds to troponin
Which of the following is responsible for muscle relaxation?
Calcium ions are removed from the sacroplasm by active transport
Deep posterior extensor of the wrist and fingers
Controls the thumb and index finger
The extensor muscle that branches to form for tendons on the back of the hand is
Extensor digitorum
T or F: Keeping the humeral head centered within the glenoid cavity requires that the muscle be in separate planes.
False It requires that the muscles be in same plane as the head of the humerus.
T or F: The teres major muscle is one of the two posterior muscles that cross the glenohumeral joint.
False Only the teres major muscle crosses the glenohumeral joint.
T or F: Both adduction and abduction require the deltoid muscle for action.
False The deltoid muscle is the prime mover for abduction.
T or F: The rotator cuff muscles increase upward pressure from the humerus on the acromion process of the scapula.
False The rotator cuff muscles minimize upward pressure against the acromion.
T or F: The rotator cuff is a term used to describe the group of muscles and tendons that stabilize and reinforce the pectoral girdle.
False The rotator cuff stabilizes and reinforces the glenohumeral joint.
The two heads of the biceps brachii combine to insert on the
Radial tuberosity
which deep posterior extensor of the wrist originates on the radius and ulna and enter interosseous membrane
The abductor pollicis longus
according to this graft
The muscle fiber is not allowed to relax between stimuli
which of the following statements about muscles of the forearm is true
The pronator teres originates on the medial epicondyles and inserts on the radius
How many distinct sets of fibers compose the deltoid muscle?
Three
T or F: Contraction of the pronator teres and the pronator quadratus results in forearm pronation.
True
T or F: Muscle of extension for the forearm is located posteriorly.
True
T or F: One of the origin sites for the trapezius muscle is the external occipital protuberance.
True
T or F: The primary function of the pectoral girdle is to provide the only connection between the arm and the axial skeleton.
True
T or F: The rotator cuff muscles act to stabilize the humerus.
True
T or F: The subscapularis muscle inserts on the lesser tubercle of the humerus.
True
T or F: The teres minor muscle provides for external rotation of the humerus.
True
T or F: The two heads of the biceps brachii muscle converge distally to insert on the radial tuberosity.
True
What are the components of a triad?
Two terminal cisternae of the sarcoplasma reticulum (SR) and one T-tubule
end plate potential
a depolarization caused by sodium ion movement into the cytosol.
The teres major adducts the arm but does not_____the arm
abduct
The middle fibers of the Deltoid muscle
abduct arm
Movement of the shoulder away and laterally from the body is called _____________.
abduction
tensor fascia latae is involved in hip
abduction
epi-
above
mechanism ends neural transmission at neuromuscular junction
ach diffuses away from synaptic cleft ach is broken down into acetic acid and choline by the enzyme acettlcholinesterase
the pettiness muscle ___ the thought ans is inverted by the ___nerve
addicted and flexes ;fibular
A reduction in the lateral angle of the glenohumeral joint in relation to the anatomical position would be called __________.
adduction
actions of the latissimus dorsi muscle?
adduction, extension, internal rotation, horizontal abduction
which of the following is not true of the deep fascia of the leg
an insertion for the majority of the lower leg muscles
smallest of the posterior extensors of the elbow joint
anconeus
The muscles of the shoulder joint are divided into all of the following groups except the _____________.
anterior flexors
The origin of the rectus femoris is the
anterior inferior iliac spine
the origin of the sartorius muscle is from the ___ slime
anterior superior iliac
The pectoralis muscle originates on the _____________.
anterior surfaces of ribs 3 to 5
The deltoid muscle fibers are separated into
anterior, middle, posterior
At the completion of supinator action the palm is turned
anteriorly
insertion of extensor carpi radialis longus
base of 2nd metacarpal
The anterior scapular muscles include the _____________ muscle(s).
biceps brachii coracobrachialis deltoid
Hyperextension of the elbow would result in damage to the _____________.
biceps brachii muscle
The most powerful muscle of the flexors is the _____________.
brachialis
Which of the following muscles is not part of the shoulder
brachialis
The anterior flexors consist of the _____________ muscle(s).
brachialis, brachioradialis and biceps brachii
The two heads of the gastrocnemius muscle converge to insert onto __________.
calcaneus
the soleus and the gastrocnemius share an insertion in the
calcaneus
The components of the pectoral girdle include _____________.
clavicle and scapula
The pectoralis major muscle can be divided into groups of fiber superior or _____and inferior or _____
clavicular sternocostal
Temporalis, along with the masseter, __________.
closes the jaw
types of contraction
concentric, eccentric, isotonic -muscle lengthens isometric -muscle is contracting but is neither lengthening nor shortening
The coracobrachialis muscle originates on the _____________.
coracoid process of the scapula
The brachialis muscle is located _____to the biceps brachii muscle
deep
The forearm muscles can be divided into interior flexors and posterior extensors as well as
deep and superficial layers
Of the nine muscles that cross the shoulder joint and insert on the humerus which muscle is considered to be a prime mover
deltoid
The prime movers of glenohumeral joint flexion are the _____________ muscles.
deltoid and the pectoralis major
action of highlighted muscle
depressed hyoid
Digastirc omohyoid sternothyroid thyrohyoid
diagastric
insertion of extensor digitorum
distal phalanges of fingers 2-5
Muscles of the shoulder can be divided into three separate groups based on _____________ relationships.
distribution and functional
the structure highlighted
epimysium
The main action of the fibularis longus is to
evert foot
Which of the following is NOT a role of ATP in muscle contraction?
exposing myosin binding sites on actin
The action of the extensor digitorum longus muscle is to
extend digits
vastus intermedius ___ the leg at the knee
extends
The semimembranosus ______the thigh at the hip and ______the leg at the knee
extends ;flexes
The gluteus maximus is the most powerful muscle during
extension
The prime mover of wrist extension is the
extensor digitorum
The two muscles that insert on the fifth phalanx or on the fifth metatarsal are the __________.
extensor digo toruń longus and fibularis tertius
which structure is highlighted myofibril fiber perimysium fascicle
fascicle
vastus lateralízalo is inverted by the
femoral nerve
eversión of the foot is a function of the
fibularis longus
sacro
flesh
Both heads of the biceps femoris muscle __________.
flex the leg at the knee
The soleus muscle the foot at the ankle and is innervated by the
flexes ; tibial nerve
flexor carpi ulnaris action
flexes wrist and adducts hand
A reduction in the anterior angle of the glenohumeral joint in relation to the anatomical position would be _____________.
flexion
Movement at the elbow joint is summarized as _____________.
flexion and extension
Brachioradialis is a strong forearm
flexor
superficial flexor muscles of the forearm is most lateral
flexor carpi radialis
which muscle is a superficial anterior flexor muscle
flexor digitorum superficialis
which muscle of the rest in fingers is deep interior
flexor pollicis longus
wrist abduction occurs through the actions of
four
abduction requires the action of two muscles that adduction requires action of
four muscles
The soleus muscle shares an insertion with the
gastrocnemius muscle
The prime mover of hip extension is the __________.
gluteus maximus
Infraspinatus inserts on the ___ of the humerus
greater tubercle
The insertion of the teres minor is on the
greater tubercle of humerus
insertion of supraspinatus
greater tubercle of humerus
origin of flexor carpi radialis
humerus
what are the three heads of the flexor digitorum superficialis
humoral radial ulnar
The majority of the fibers of the gluteus maximus insert onto the
iliotibial tract
excitation contraction coupling results in an increase of calcium ion concentration
in the custom of the muscle fiber
Carpal tunnel syndrome is characterized by
inflammation of the flexor retinaculum and/or tendon sheaths
The long head of the triceps brachii muscle originates on the _____________.
infraglenoid tubercle of the scapula
the flexor hallucinations longus muscle originates on the
interosseous membrane
latissimus dorsi inserts
intertubercular groove of humerus
All fibers of the pectoralis major muscle converge on the lateral edge of the__________.
intertubercular sulcus
The actions of the muscles that cross the hip do not include
inversión
The tibialis anterior muscle dorsiflexes the foot at the ankle and also assists in of the foot
inversión
The most flexible joint in the body
is the shoulder joint
The long head of the biceps femoris muscle originates on the
ischial tuberosity
hamstring muscles originate on the
ischial tuberosity
The arrow indicates the direction of the electrochemical gradient for
k+
The most important function of the rotator cuff muscles is to _____________.
keep the humeral head centered within the glenoidal cavity
Tensor Fasica Latae stabilizes the hip joint and the ___ joint
knee
The rectus femoris muscle extends the leg at
knee
The trapezius muscle may be separated into all the following groups except
lateral
The origins of the lateral head of the gastrocnemius muscle are the
lateral condyle and posterior surface of the femur
origin of supinator
lateral epicondyle of humerus
The actions of the rhomboid major on the scapula do not include
lateral rotation
The prime movers of the shoulder joint are
latissimus dorsi, pectoralis major, and deltoid
The posterior axial muscle that crosses the glenohumeral joint is the
latissimus dorso
Both the Psoas major muscle and iliacus muscle insert on the __________.
lesser trochanter of the femur
Iliopsoas inserts onto the ________.
lesser trochanter of the femur
The subscapularis muscle inserts on the
lesser tubercle of humerus
The four muscles that comprise the posterior group of the pectoral girdle are the _____________.
levator scapulae, rhomboideus minor, rhomboideus major, and trapezius
The organ that the vastus medialis muscle shares with the vastus lateralis is the
linea aspera of the femor
Masseter inserts onto the angle and ramus of the ______.
mandible
Buccinator has origins on both the _______ and the ______.
mandible; maxilla
insertion of the fibularis longus is the
medial cunieform
The pectoralis minor muscle is innervated by the
medial pectoral nerve
The key actions of the pectoralis major muscle are __________.
medial rotation and adduction
what structure is highlighted muscle fibers capillaries motor axons motor end plates
motor axons
what structure is highlighted motor end plates mitochondria motor axons nuclei
motor end plates
myo
muscle
active ingredient of botox, botulinum toxin blocks the release of Ach from the axon terminal . an overdose of botox will most likely result in
muscle paralysis at the site of injection
The protein that binds to actin when tropomyosin moves off the active sites of actin is
myosin
A crossbridge forms when:
myosin head binds to actin
The extensor hallucis longus muscle inserts on digit
one
Movement not associated with the scapula
opposition
serratus anterior
originates from ribs 1-8 and inserts on the anterior vertebral border of the scapula
pectoralis minor
originates on the anterior surfaces of ribs 1-5 and inserts on the coracoid process of the scapula
Palmaris longus inserts on the
palmart aponeurosis
Anterior muscles of the pectoral girdle include the _____________.
pectoralis minor and the serratus anterior
what structure is highlighted sarcolemma endomysium epimysium perimysium
perimysium
the most powerful movement at the ankle joint is ___ and the ___is one of the prime movers if this movemtn
plantar flexión ; gastrocnemius
to allow for flexión _____ unlocks the knee joint
popliteus
The semitendinosus muscle is innervated by the ___nerve
posterior
insertion of pectineus is ___ and on the ___
posterior fémur
The flexor hallucis longus muscle originates from the
posterior surface of the fibular shaft
The biceps femoris is located in the
posterior thigh
All fibers the semimembranosus muscle converge lo insert on the
posterior tibia
The ball and socket joint in the hip is similar to the ball and socket joint of the shoulder but is designed more for blank then blank
power precision
Movement of the forearm is summarized as _____________.
pronation and supination
Muscles of the forearm that function in pronation and supination are the _____________.
pronator quadratus, pronator teres, and supinator
of all the flexor muscles of the forearm the__ is the shortest
pronator teres
all fibers of the triceps brachii are innervated by the
radial nerve
The interosseous membrane is located between the
radius and ulna
origin of serratus anterior
ribs 1-8
The rotator cuff muscles provide what type of movement?
rotation
Infraspinatus muscle is included in the____muscles
rotator cuff
anterior muscles of the thigh that originate on the os coxae are
sartorius ;recutus femoris
To allow movement of the tendons within carpal tunnel zone each tendon is encased in a
sheath
the figure decpictws the contraction of
smooth muscle
Stimulation of acetylcholine (ACh) receptors by ACh will primarily result in:
sodium ions entering the muscle fiber
In the absence of ATP in the musclewhich of the following is most likely to occur?
some myosin heads will remain attached to actin molecules but are unable to perform power stroke
fibers of trapezius muscles are innervated
spinal accessory nerve
The rhomboideus minor muscle originates on which process of the vertebrae?
spinous process
thyrohyoid sternohyoid omohyoid sternothyroid
sternothyroid
The gluteus medius muscle is innervated by the
superior gluteal nerve
rhomboid minor muscle sits
superior to the rhomboid major
Forearm supination is the result of the __________, but is assisted by the ____________.
supinator muscle, biceps brachii muscle
Downward dislocation of the humerus from the glenohumeral joint when carrying weight is prevented by the _____________ muscle.
supraspinatus
What muscles are part of the rotator cuff?
supraspinatus infraspinatus subscapularis teres minor
narrow space between the axon terminal and motor end plate is called the
synaptic cleft
Extension of the glenohumeral joint results from the contraction of one synergist, the _____________.
teres major
The posterior scapular muscle that crosses the glenohumeral joint is the _____________ muscle(s).
teres major
The angle of the subscapularis muscle prevents _____________.
the humeral head from sliding upward out of the joint as the arm is raised
The neurons of patients with multiple sclerosis are unable to transmit action potentials down the axon. How will that affect skeletal muscle stimulation?
the muscle will not be stimulated and therefore will not contract
The posterior surface of the tibial shaft is
the origin of the flexor dígitorum longus
Predict the effect of Tetrodotoxin , a powerful blocker of voltage-gated sodium ion channels
there will be no action potential in muscle fiber
muscles that act on the knee joint form most of the mass of the
thigh
why are the muscles that move the fingers and wrist located in the forearm
this design allows the hand to maintain fine motor control and strength without interference of bulky muscles
The tibialis posterior muscle originates at which three locations?
tibia fibula interosseous membrane
The semitendinosus muscle is innervated by the______ nerve
tibial
The flexor digitorum longus muscle is innervated by the
tibial nerve
The gastrocnemius muscle is innervated by the
tibial nerve
the prime mover of dorsiflexion is the
tibialis anterior
The origins of the levator scapula are from the ______of four cervical vertebrae
transverse processes
The prime mover of elbow extension is the
triceps brachii
in preparation for contraction calcium ions bind to
tropinin
T/F The anterior axial muscle that crosses the glenohumeral joint is the pectoralis major muscle
true
endo
within
actions of the extensor carpi radialis brevis are localized to
wrist
