ch. 6 the muscular system

What substance is released from the axon terminal into the synaptic cleft at the neuromuscular junction? Calcium ions Sodium ions Acetylcholinesterase Acetylcholine

Acetylcholine

Select all of the true statements regarding ATP regeneration during muscle activity. SELECT ALL THAT APPLY Aerobic respiration requires oxygen and produces the highest yield of ATP. Anaerobic glycolysis is the slowest mechanism for ATP generation. One of the pathways for ATP regeneration is direct phosphorylation of ADP by creatine phosphate. At rest and during light exercise, ATP is regenerated almost entirely by anaerobic pathways.

Aerobic respiration requires oxygen and produces the highest yield of ATP. One of the pathways for ATP regeneration is direct phosphorylation of ADP by creatine phosphate.

Assign each muscle to its corresponding pattern of fascicle arrangement. Rectus femoris Pectoralis major Orbicularis oris Biceps brachii Sartorius Circular Parallel Fusiform Pennate Convergent

Circular - Orbicularis oris Parallel - Sartorius Fusiform - Biceps brachii Pennate - Rectus femoris Convergent - Pectoralis major

Which muscle is the prime mover of arm abduction? Latissimus dorsi Deltoid Biceps brachii Triceps brachii

Deltoid

Select the true statement regarding skeletal muscle attachments. The insertion is the immovable or less movable attachment. Each muscle attaches to bone or another connective tissue at no fewer than three points. During contraction, the insertion moves toward the origin. The origin is the more movable attachment.

During contraction, the insertion moves toward the origin.

Select the anterior abdominal muscle. External oblique Latissimus dorsi Rectus femoris Biceps brachii

External oblique

Select all of the terms or phrases that characterize cardiac muscle. Forms heart walls Striated Cylindrical cells Intercalated discs Involuntary Multinucleate

Forms heart walls, Intercalated discs, Involuntary, Striated

Select all of the functions of skeletal muscle. Moves food along the gastrointestinal tract Maintains posture Generates heat Stabilizes joints Transports blood

Generates heat, maintains posture, stabilizes joints

Select all of the characteristics and examples of isometric contraction. Muscle shortens Lifting a baby Muscle tension increases Muscle lengthens No movement occurs Holding a baby in one position

Holding a baby in one position No movement occurs Muscle tension increases

Which of the following is a chewing muscle? ANSWER Orbicularis oris Masseter Platysma Zygomaticus

Masseter

Select all of the true statements regarding tetanus. Tetanus results from the simultaneous activation of multiple motor units. Tetanus results from the random contraction of alternating motor units. Tetanus produces smooth and prolonged muscle contractions. Tetanus results from the increased frequency of stimulation delivered to the muscle. Tetanus produces more forceful muscle contractions.

Tetanus produces more forceful muscle contractions; tetanus produces smooth and prolonged muscle contractions; tetanus results from the increased frequency of stimulation delivered to the muscle.

In a skeletal muscle fiber, the sarcomere is a repetitive unit that consists of the entire region between the __________. ANSWER Z discs H zones dark (A) bands light (I) bands

Z discs

the biceps brachii is located on the ___ arm

anterior

The ____is an anterior arm muscle that flexes the forearm.

biceps brachii

The muscle that facilitates flexion of the forearm is the __________. triceps brachii biceps femoris biceps brachii buccinator

biceps brachii

The muscle that facilitates flexion of the forearm is the __________. biceps brachii buccinator biceps femoris triceps brachii

biceps brachii

The_____ is an anterior arm muscle. Rectus femoris Biceps brachii Latissimus dorsi External oblique

biceps brachii

The ____ is a hamstring group muscle on the posterior thigh that extends the thigh and flexes the leg.

biceps femoris

The _____ is a cheek muscle that compresses the cheek as in whistling.

buccinator

The sarcoplasmic reticulum releases __________ when the muscle fiber is stimulated to contract. calcium ions acetylcholine sodium ions ATP

calcium ions

The _____ muscle is the prime mover of arm abduction. Abduction moves the arm away from the midline of the body. The ___ is a triangle-shaped, fleshy muscle that forms the rounded shoulder muscle mass. This is a common site for intramuscular injections.

deltoid

The anterior abdominal muscles include the _____, _____, ____, and ______. Together, these muscles reinforce the body trunk and protect the abdominal contents.

external oblique, internal oblique, rectus abdominis, transversus abdominis

An important site for intramuscular injections in the hip is the __________. ANSWER gluteus medius gluteus maximus gluteus minimus vastus lateralis

gluteus medius

Which special movement turns the sole of the foot medially? Plantar flexion Inversion Eversion Dorsiflexion

inversion

The ____ is a lower back muscle. Rectus femoris Biceps brachii Latissimus dorsi External oblique

latissimus dorsi

The ____ muscle is a triangular muscle of the lower back. This muscle is a prime mover of arm extension and a powerful arm adductor.

latissimus dorsi

Which of the following refers to one neuron and all the skeletal muscle cells it stimulates? Synaptic cleft Neuromuscular junction Muscle fiber Motor unit

motor unit

A skeletal muscle cell is also called a __________. sarcomere myofibril myofilament muscle fiber

muscle fiber

Cross bridges form when __________. ANSWER calcium ions bind to regulatory molecules on the thin filaments. ATP molecules bind to myosin heads on the thick filaments. adjacent sarcomeres attach at Z discs along the myofibrils. myosin heads bind to actin molecules on the thin filaments.

myosin heads bind to actin molecules on the thin filaments.

A fascicle is wrapped by a layer of connective tissue called __________. endomysium epimysium perimysium aponeurosis

perimysium

the biceps femoris is a hamstring group muscle on the _____ thigh that extends the thigh and ____ the leg.

posterior , flexes The biceps femoris is a hamstring group muscle on the posterior thigh that extends the thigh and flexes the leg.

When the biceps brachii acts as the __________ to flex the forearm, the triceps brachii on the opposite side of the humerus acts as the __________ by opposing this movement. antagonist; prime mover prime mover; fixator prime mover; antagonist fixator; antagonist

prime mover; antagonist

The _____ is a quadriceps muscle of the anterior thigh. Rectus femoris Biceps brachii Latissimus dorsi External oblique

rectus femoris

The plasma membrane of a muscle cell is called the __________. sarcolemma sarcomere sarcoplasm sarcoplasmic reticulum

sacrolemma

biceps brachii originates on the ____ and inserts on the ___.

scapula , radius

When comparing skeletal, cardiac, and smooth muscle, which of the following characteristics is unique to just one muscle type? Under involuntary control Spindle-shaped cells Uninucleate cells Striated appearance

spindle shaped cells

The muscle whose action is dorsiflexion and inversion of the foot is the __________. sartorius tibialis anterior biceps femoris rectus femoris

tibialis anterior

The ___ ____is a posterior arm muscle that extends the forearm.

triceps brachii

The ___ is a powerful forearm extensor located on the posterior arm. This muscle is an antagonist to the biceps brachii.

triceps brachii