A&P Muscular System

Which of these pathways to regenerate ATP during muscle activity is the fastest

) anaerobic glycolysis and lactic acid formation

During skeletal muscle contraction, myosin cross bridges attach to active sites of

actin filaments

A muscle twitch results when the muscle is stimulated so rapidly that no evidence of relaxation is seen.

FALSE

A prime mover of the arm that acts in adduction is the deltoid.

FALSE

An aponeurosis is a ropelike piece of muscle fascia that forms indirect connections to muscles of the leg.

FALSE

Cardiac muscle fibers are relatively short, tapering cells within a single centrally located nucleus

FALSE

Dorsiflexion and plantar flexion are synergistic actions

FALSE

Lactic acid results from aerobic respiration

FALSE

Plantar flexion at the ankle joint is accomplished by the tibialis anterior muscle.

FALSE

Skeletal muscle is considered involuntary because it is the only type of muscle usually subject to conscious control.

FALSE

Supination and pronation refer to up and down movements of the foot at the ankle.

FALSE

The epimysium covers individual muscle fibers

FALSE

The insertion of the biceps brachii muscle is on the radius.

FALSE

There are 206 skeletal muscles in the human body

FALSE

Thick filaments are made of a protein called actin

FALSE

A contraction in which a skeletal muscle does not shorten but its tension increases is called isometric

TRUE

A nerve cell and all the muscle cells that it stimulates are referred to as a motor unit.

TRUE

A sustained partial contraction of skeletal muscle is called muscle tone

TRUE

One of the important functions of skeletal muscle is to generate heat

TRUE

Skeletal muscles need nerve stimulation for contraction to occur

TRUE

The bicpes brachii muscle is named for the two heads that orginiate from the shoulder girdle.

TRUE

The deepest muscle of the abdominal wall is the transversus abdominis.

TRUE

The neurotransmitter used by the nervous system to activate skeletal muscle cells is acetylcholine

TRUE

When a muscle fiber contracts, the I bands diminish in size, the H zones disappear, and the A bands move closer together but do not diminish in length.

TRUE

While doing "jumping jacks" during an exercise class, your arms and legs move laterally away from the midline of your body. This motion is called

abduction

Which of these events must occur first to trigger the skeletal muscle to generate an action potential and contract

acetylcholine (ACh) causes temporary permeability to sodium

Neurotransmitters are released upon stimulation from a nerve impulse by the

axon terminals of the motor neuron

A nursing infant develops a powerful sucking muscle that adults also use for whistling or blowing a trumpet called the

buccinator

The insertion of the gluteus maximus is the

femur

Which of the following muscles is not involved in dorsiflexion and/or plantar flexion of the foo

iliopsoas

Paralysis of which of the following would make an individual unable to flex the thigh

iliopsoas and rectus femoris

The condition of skeletal muscle fatigue can be best explained by

insufficient intracellular quantities of ATP due to excessive consumption

Which one of the following does NOT compress the abdomen

latissimus dorsi

What is NOT a criteria generally used in naming muscles

method of attachment of the muscle to bone

Anaerobic glycolysis occurs without

oxygen

A muscle located on the ventral (anterior) side of the body is the

pectoralis major

Which one of the following muscle actions would NOT be classified as an ISOTONIC contraction

pushing against a stationary wall

The major function of the sarcoplasmic reticulum in skeletal muscle contraction is to

regulate intracellular calcium concentration

An elaborate and specialized network of membranes in skeletal muscle cells that function in calcium storage is the

sarcoplasmic reticulum

Creatine phosphate (CP) functions within the muscle cells by

storing energy that will be transferred to ADP to resynthesize ATP as needed

Which of these muscles is not responsibile for flexion or extension of the arm?

A) biceps brachii B) triceps brachii C) brachialis D) platysma E) latissimus dorsi Answer: D

Which of the following muscles are antagonists

A) biceps brachii and triceps brachii B) bicpes femoris and biceps brachii C) vastus medialis and vastus lateralis D) masseter and temporalis E) gastrocnemius and soleus Answer: A

Which one of the following muscles is involved in abduction of the arm at the shoulder joint

A) deltoid B) biceps brachii C) triceps brachii D) latissimus dorsi E) pectoralis major Answer: A

Paralysis of which of the following would make an individual unable to flex the knee:

A) hamstring muscle group B) gluteal muscle group C) gastrocnemius D) sartorius E) iliopsoas Answer: A

Which of the following muscles adducts the thigh

A) peroneus muscles B) gluteus maximus C) sartorius D) quadriceps group E) adductor muscles Answer: E

The gap between the axon terminal of a motor neuron and the sarcolemma of a skeletal muscle cell is called the

synaptic cleft

A muscle group that works with and assists the action of a prime mover is a(n):

synergist only

The striations that give skeletal muscle its characteristic striped appearance are produced, for the most part, by

the arrangement of myofilaments

Which of the following muscles closes the jaw

the masseter and the temporalis

A skeletal muscle twitch differs from a tetanic contraction in that

the muscle twitch is a brief and "jerky" movement, while the tetanic contraction is prolonged and continuous

Which one of the following is the action of the orbicularis oris

closes, purses, and protrudes the lips

Sandra is playing the piano for her recital. Which muscle is not involved in the movement of her hands and/or fingers

extensor digitorum longus

Which of the following muscles inserts on the calcaneus

the soleus