Muscular System Lecture Exam

A muscle working in opposition to another muscle.

An antagonist is:

Muscle tone

An example of a partial but sustained contraction would be:

Dendrites

Branched nerve fibers that convey impulses toward the cell body of a neuron are called:

Myosin

ADP molecules on the surface of actin serve as active sites for the formation of cross bridges with molecules of:

Creatine phosphate supplying energy to regenerate ATP from ADP and phosphate.

ATP is related to creatine phosphate by:

Myosin heads

ATPase is found in:

Slow, fatigue-resistant muscle fibers

Activities such as swimming and running are most likely to stimulate development of:

Endomysium

Each muscle fiber is directly surrounded by connective tissue called the:

Serotonin

Excessive sleeping is most likely due to the presence of too much which neurotransmitter?

Latent period

In a recording of a muscle twitch, the delay between the time a stimulus is applied and the time the muscle responds is called the:

Depolarized

In response to a stimulus, if the membrane potential becomes more negative than resting potential, we say the membrane is:

Mandibular

Which of the following is not a muscle of mastication?

Acetylcholine

Myasthenia graves reflects a deficiency in communication by ________ because receptors for this neurotransmitter have been destroyed.

Schwann cells

Myelin sheaths on the outside of many axons are contributed by:

Axon

Nerves impulses always travel to the brain through _______ fibers.

Motor end plates

Neurotransmitters are stored in vesicles within:

Lack of ATP, which prevents muscle relation.

Rigor mortis that occurs in skeletal muscles a few hours after death is due to:

The strength of impulses carried along a single nerve fiber can vary with the strength of their stimulus.

Select the INCORRECT statement about nerve impulse conduction.

Smooth muscle fibers

Short muscle cells with centrally located nuclei are:

Are under involuntary control

Sooth muscle and cardiac muscle are similar in that they both:

Oligodendrocytes

The _______ are types of neurological cells that provide myelin in the central nervous system.

Transverse (T) tubules

The _________ are an invagination of the muscle cell's sarcolemma.

Actin myofilaments

The active sites to which cross-bridges attach are found on the:

When a muscle fiber contracts, it contracts completely.

The all-or-none response means

Oxygen debt

The amount of oxygen needed to support the conversion of lactic acid to glucose is called the:

Brachialis

The antagonist to the triceps brachii is the:

Summation

The application of multiple stimuli to a muscle is defined as the process called:

Semitendonosus

The biceps femurs is one hamstring muscle located on the back of the thigh. Which muscle is the other hamstring?

Preventing the release of acetylcholine

The botulinus toxin that causes botulism acts by:

Contractility

The capacity of a muscle cell to shorten forcefully is known as:

Sensory neurons

The cells that conduct messages towards the brain are the:

Myosin myofilaments

The crossbridges involved in muscle contraction are located on the:

Ruptured blood vessels

The discoloration and swelling that may accompany a muscle strain is due to:

One Z line to the next Z line

The segment of a myofibril that is called a sarcomere runs from

Sarcomere arrangement

The striated appearance of skeletal muscle results from the:

Tone

The term ____ refers to the constant state of contraction of a certain number of fibers within a muscle.

Trapezius

The triangle shaped muscle which antagonizes the sternocleidomastoid is the:

Smooth muscle

The type of muscle cell that lacks transverse tubules, has a single nucleus, and is under voluntary control is:

Multiunit smooth muscle

The type of muscle found in the irises of the eyes in the blood vessels is called:

Orbicular

The type of muscle that functions as a sphincter is:

Latent period

The very brief moment following stimulation when a muscle remains unresponsive to additional stimulation is called the:

Minimal stimulus needed to solicit a muscular contraction.

Threshold stimulus is defined as:

Skeletal muscle fibers

Transverse tubules and sarcoplasmic reticulum are well developed in:

Has a calcium-binding site.

Troponin

Spinal nerve

Which term does not belong with the others? Brain Spinal cord CNS Spinal nerve

Actin

Which term is the smallest subdivision in this group? Filament Fibril Fiber Actin

Fixators

When you "pull in your tummy" and compress your abdomen, you use the rectus abdomens, external abdominal oblique, internal abdominal oblique, and transverse abdomens muscles. This is an example of muscles working as:

Cardiac muscle

Which type of muscle tissue causes contraction of the heart?

Tetanic

Which description of muscle contraction means that all of the fibers within a muscle are fully contracted?

Spinal cord

Which items should not be grouped together? Spinal nerve Cranial nerve Spinal cord PNS

Orbicularis oris

Which muscle enables you to pucker your lips for a kiss?

Biceps brachii

Which muscle is the strongest flexor of the elbow?

Moving your feet in walking

Which of the following actions is caused by contraction of skeletal muscle?

Skeletal muscle

Which type of muscle tissue is multinucleate?

Skeletal muscle

Which type of muscle tissue would cause flexion and extension of the arm?

Ependyma

Which type of neurological cells help regulate the composition of cerebrospinal fluid?

Accelerator neurons

Which types of neurons are likely to increase muscular activities?

Cardiac muscle is self-excitatory

Why can cardiac muscle fibers contract for longer periods than skeletal muscle fibers?

A motor neuron and the muscle fibers it innervates

A motor unit is made up of:

ATP

A muscle cramp is likely due to lack of:

Multipolar and motor

A neuron with many nerve fibers arising from its cell body that carries impulses away from the brain would be classified as:

The muscle that does most of the movement.

A prime mover is:

One Z disk to an adjacent Z disk.

A sarcomere extends from:

A unit within a myofibril

A sarcomere is best described as:

Anaerobic threshold

A shift in metabolism that breaks down pyretic acid to produce lactic acid is called:

A group of muscles that work together to cause movement.

A synergist is:

Cordlike and connecting muscle to bones; A broad, fibrous sheet of connective tissue that connects muscles to muscles.

A tendon is characterized by being ______, whereas an aponeurosis is characterized by being _______.

Sodium; potassium

At resting potential, the ion distribution inside and outside of a neuron is such that ________ ions are most abundant on the outside of the cell, while ________ ions are most abundant on the inside of the cell.

Contracts more slowly and relaxes more slowly

Compared to skeletal muscle, smooth muscle:

Supply energy for the synthesis of ATP

Creatine phosphate serves to:

Schwann cell

Cut neurons possess limited capabilities for regeneration. The type of neurological cell that aids regeneration by forming a regeneration tube to help reestablish the former connection is the

Synaptic cleft

Into what does the neuron release its neurotransmitter at the neuromuscular junction?

Occurs in the walls of the stomach and intestines

Multiunit smooth muscle:

Sarcomeres

Muscle fibers are basically a collection of:

Synergists

Muscles that act to cause similar movements are called

Atrophy

Muscles that are not used, may degenerate or undergo a process of:

When a person is fully at rest, none of her muscles are contracting. (NOT true)

One of the following statements about muscular responses is not true.

The inability of myoglobin molecules to store enough oxygen when skeletal muscles are used strenuously for a minute or two.

Oxygen debt in muscles may develop because of:

Decompose

The enzyme cholinesterase causes acetylcholine to:

Transverse tubules

The impulse that triggers a contraction travels deep into a muscle fiber by means of:

Recruitment

The increase in the number of motor units activated when the intensity of stimulation increases is called:

The end of the muscle where the action occurs

The insertion is:

Perimysium

The layer of connective tissue that separates the muscle tissue into small sections is called the:

Norepinephrine

The levels of which neurotransmitter are affected by he mood-elevator, cocaine?

Buccinator

The major muscle lining the cheek is the

Acetylcholine

The most common neurotransmitter in the body is:

Rhomboideus major

The muscle that enables you to elevate and adduct your scapula is the:

Schwann cell

The myelin sheath around a neuron is actually produced by the:

The stationary end of the muscle

The origin is:

Myofilament movement.

The role of ATP in muscle contraction is to supply energy for:

To transmit muscle impulses into the cell interior.

What is the function of the transverse tubules?

There is a reduction in capillary networks. The number of mitochondria decreases. The size of actin and myosin filaments decreases. *All of these occur.*

When a muscle undergoes atrophy in response to disuse,

Calcium is released from the sarcoplasmic reticulum

When a nervous impulse travels from a neuron to a muscle cell, what happens next?

Seconds

When a neuron reaches action potential, it depolarizes and depolarizes in an amount of time on the order of:

Involuntary

Which of the following does NOT belong with the others? Striated Skeletal Multinucleated Involuntary

Respiration

Which of the following is NOT a function of skeletal muscle?

Red muscles contain more myoglobin than white.

Which of the following is NOT true when comparing red and white muscle types?

Palmaris longus

Which of the following is unique in that its insertion is to fascia rather than bone?

The cross bridges bind to the actin and shorten the sarcomeres

Which of these statements is correct regarding muscle contraction?

Acetylcholinesterase

________ is responsible for degrading acetylcholine so that it does not remain in the synapse.