A&P Final Exam

Place these structures of the skeletl muscle in order from largest to smallest: 1. fascicle 2. myofilament 3. muscle fiber (cell) 4.myofibril 5. sarcomere

1. Fascicle 3. Muscle fiber (cell) 4. Myofibril 5. Myofilament 6. Sarcomere

Acetylcholine is...

A neurotransmitter that stimulates skeletal muscle

The mechanical force of contraction is generated by...

A sliding of thin filaments past thick ones

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

Abduction

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

Acetylcholine (ACh) causes temporary permeability to sodium

During skeletal muscle contraction, myosin heads attach to active sites of...

Actin filaments

What is the opposite to abduction is?

Adduction

The light and dark banding patterns send in striated muscle, like skeletal muscle, originate from...

Alternating light and dark bands

Endomysium covers...

An individual muscle cell

Neurotransmitters are released upon stimulation from a nerve impulse by the...

Axon terminals of the motor neuron

Which muscle is NOT involved in the movement of the hands and/or fingers?

Extensor digitorum longus

There is no possibility of damaging the spinal cord below the third lumbar vertebra.

False

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

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.

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

False.

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

False.

The deltoid is a pime mover of arm adduction.

False.

The hamstring group inserts into the distal tibia.

False.

Thick filaments are made of a protein called actin.

False.

Cardiac and smooth muscles both have striations.

False. Cardiac and skeletal muscles both have striations.

Smooth muscles activity generates heat to help maintain body temperature.

False. Skeletal muscles activity generates heat to help maintain body temperature.

A muscle is located on the ventra/anterior side of the body is of...

Pectoralis major

The plasma membrane of a skeletal muscle cell is called the...

Sarcolemma

Which of the following can actually shorten during a muscle contraction?

Sarcomeres

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

Sarcoplasmic reticulum

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

Sartorius

What is the origin of the deltoid muscle?

Scapular spine and clavicle

Voluntary muscle tissue is...

Skeletal muscle

Which type of muscle tissue responds the fastest to stimulations to contact?

Skeletal muscle tissue

Creatine phosphate (CP) functions within the muscle cells by...

Storing energy that will be transferred to ADP to re-synthesize ATP as needed.

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

Synaptic cleft

A sarcomere is...

The contractile unit between two Z discs

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 continous

Which one of the following is composed of myosin protein?

Thick filaments

Cardiac muscle:

Tissue found only in the heart; composed of branching cells and intercalated discs

Smooth muscle:

Tissue that forms valves to regulate the passage of substances though internal body openings; activates arrector pili muscles which stand hairs on end; perform very slow, sometimes rhythmic, contractions

All types of muscle have endomysium covering individual muscle cells.

True

A sustained partial contraction of skeletal muscle is called muscle tone.

True.

Aerobic respiration requires the use of oxygen to generate ATP.

True.

Biceps brachii, brachialis, and brachioradialis all cause arm flexion at the elbow joint.

True.

Muscle development in babies occurs in a cephalic/caudual direction.

True.

Oxygen debt promotes lactic acid accumulation on muscles from anaeobic cellular respiration.

True.

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

True.

The effect of the neurotransmitter on the muscle cell membrane is to temporarily modify its permeability of ions such as Na+ and K+.

True.

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

True.

The sacroplasmic reticulum wraps like a sleeve around the myofibril and stores and releases calcium

True.

The striations seen in skeletal muscle are actually alternating A and I bands.

True.

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

True.

A single, brief, jerky muscle contraction is termed...

Twitch

Skeletal muscle:

Voluntary muscle tissue; multinucleate; maintains posture, body position, stabilizes joints, and regulates body temperature

Muscles and glands are:

effectors

A muscle group that works with and assists the action of a prime mover is a...

synergist only

Which of the following muscles are antagonists?

Biceps brachii and triceps brachii

Which of the following muscles closes the jaw?

Both masseter and temporalis

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

Buccinator

Why are calcium ions necessary for skeletal muscle contraction?

Calcium triggers the binding of myosin to actin

Which one of the following is the action of the orbicularsis oris?

Closes, purses, and protrudes the lips

Isometric contractions produce...

Contractions

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

Deltoid

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

Direct phosphorylation of ADP by creatine phosphate

Which of the following is NOT a function of the muscular system?

Hemotopoiesis

Which of the following muscles is NOT involved in dorsiflexion and/or plantar flexion of the foot?

Iliopsoas

Smooth muscle cells are...

Involuntary

What is the main function of the quadriceps femoris group?

Knee extension

Which of the the following does NOT compress the abdoment?

Latissimus dorsal

Which congentil muscle disease results from the degeneration and atrophy of muscles?

Muscle dystrophy

Which one of the following is NOT a criteria generally used in naming muscles?

Number of origins of the muscle

Anaerobic glycolysis occurs without...

Oxygen