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