Chapter 6! The Muscular System Test

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

1, 3, 4, 5, 2

When a skeletal muscle is fully contracted, the __________ are closer to the thick filaments.

Z discs

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 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 causes temporary permeability to sodium

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

actin filaments

The movement opposite abduction is

adduction

The light and dark banding pattern seen in striated muscle, like skeletal muscle, originate from

alternating light and dark bands

Endomysium covers

an individual muscle cell

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

anaerobic glycolysis and lactic acid formation

Neurotransmitters are released upon stimulation from a nerve impulse by the

axon terminals of the motor neuron

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 orbicularis oris

closes, purses, and protrudes lips

Muscle tissue has the ability to shorten when adequately stimulated, a characteristic known as ________.

contractility

Isometric contractions produce

contractions and movement but no shortening

The heads of the myosin myofilaments are called _____________ when they link the thick and thin filaments together during skeletal muscle contraction

cross bridges

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

deltoid

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 is NOT a function of the muscular system

hematopoiesis

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

iliopsoas

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

iliopsoas

The condition of skeletal muscle fatigue can be best explained by

insufficient intracellular quantities of ATP due to excessive consumption

Smooth muscle cells are

involuntary

Contractions in which muscles do not produce movement or shortening are termed __________.

isometric

What is the main function of the quadriceps femoris group

knee extension

Which one of the following does NOT compress the abdomen

latissmius dorsi

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

method of attachment of the muscle to bone

Which congenital muscle disease results from the degeneration and atrophy of muscles:

muscular distrophy

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

pectoralis major

creatine phosphate (CP) functions within the muscle cells by

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

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

synaptic cleft

The gap between the motor neuron and the muscle fiber it supplies at the neuromuscular junction 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 epimysium covering on the outside of the muscle can blend into cordlike _________ or sheetlike __________

tendons; aponeuroses

A smooth, sustained contraction is called

tetanus

A sacromere 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 continuous

Which one of the following is composed of myosin protein

thick filaments

A single, brief, jerky muscle contraction is termed

twitch

The ________ zone of a sarcomere contains no actin filaments while the skeletal muscle is at rest (noncontratile state)

H

Anaerobic glycolysis occurs without

Oxygen

Which of the following can actually shorten during a muscle contraction

sacromeres

The plasma membrane of a skeletal muscle cell is called the

sarcolemma

The plasma membrane of skeletal muscle cells is called __________

sarcolemma

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

sarcoplasmic reticulum

Which of these muscles is NOT located in the head

sartorius

What is the origin of the deltoid muscle

scapular spine and clavicle

Striated, voluntary, multinucleate muscle is classified as ____________ muscle

skeletal

Which type of muscle tissue responds fastest to simulations to contract

skeletal

Voluntary muscle tissue is;

skeletal muscle

The type of muscle tissue pictured in Firgure 6.3 is

smooth muscle