test 4

Which of the following membrane potentials represents a hyperpolarized neuron?

-100 mV

The resting membrane potential of a neuron is approximately

-70mV.

Maximal tension occurs at ____ percent of a sarcomere's resting length?

80-120

Which best describes an aponeurosis?

A broad, flat tendon

Which best describes tetanus?

A continuous contraction

Which best describes a dense body?

A sarcoplasmic structure that attaches to the sarcolemma

What powers the myosin head to pull actin along

ATP

Which is not a thenar muscle that produces thumb movements?

Abductor digiti minimi

When can a second action potential not be initiated by a larger than normal stimulus?

Absolute refractory period

Muscle contraction begins with the nervous system sending which neurotransmitter to the motor end plate?

Acetylcholine

Which of the following neurotransmitters is primarily located at the neuromuscular junction (NMJ) and stimulates muscle contraction?

Acetylcholine

Which contributed to naming the adductor longus muscle?

Action and length

Which best describes the latent period of a muscle twitch?

Action potential propagates down the sarcolemma

Which best describes the role of calcium in smooth muscle?

Activates enzymes

Which muscle does not flex the forearm?

Anconeus

Which Latin root means "to the side of?"

Apo

You are attempting to lift a heavy weight. According to the length-tension relationship, which position would allow for the strongest lift?

Arms slightly flexed

Which is characteristic of the fascicle arrangement of the majority of the muscles of the body?

Arranged in the same direction as the long axis of the muscle

Which glial cells help contribute to the blood-brain barrier?

Astrocytes

Where does summation occur?

At the axon hillock

Which of the following is not a function of the nervous system?

Automation

Which division of the nervous system is responsible for regulating heart rate?

Autonomic

Nodes of Ranvier are found on which part of the neuron?

Axon

Which is the most lateral hamstring muscle?

Biceps femoris

Which of the following neurons is the least common in the nervous system and typically found in the olfactory epithelium and retina?

Bipolar

Which of type of neuron has one main dendrite and one main axon?

Bipolar

Which of the following best describes the resting membrane potential of a neuron?

Buildup of fewer positive charges on the intracellular side of the membrane relative to the extracellular side

Which event will stimulate the release of neurotransmitters from a synaptic bulb?

Ca2+ channels open

Which is a function of the T-tubules?

Carry the action potential to the interior of the cell

Which best describes the location of the buccinator muscle?

Cheek

What usually causes muscle contraction to stop?

Closing of the voltage-gated calcium channels in the sarcoplasmic reticulum

Which property of muscle tissue allows muscle to shorten with force?

Contractility

Which muscle twitch phase is characterized by the formation of cross-bridges?

Contraction

Which of the following characteristics is true of only multi-unit smooth muscle, and not of single-unit smooth muscle?

Contraction stimulated by hormones

Which muscle moves the eyebrows?

Corrugator supercilii

Which is not a step in the sliding filament model of muscle contraction?

Cross bridges form between troponin and tropomyosin

Which is true regarding hypertrophy?

Cross-sectional diameter of muscle increases

Which muscle is the major arm abductor?

Deltoid

Which does not occur in muscle fibers during a resistance training session?

Development of high numbers of slow oxidative fibers

Which property of muscle allows it to return to its original length after contracting?

Elasticity

Where is the orbicularis oculi muscle located?

Encircling the eye

Which system is specifically responsible for controlling the smooth muscle and glandular tissue in the digestive system?

Enteric nervous system

Which of the following is responsible for the production of cerebrospinal fluid (CSF)?

Ependymal cells

Which best describes the dense irregular tissue wrapping around the outside of a muscle?

Epimysium

Which of the following neurotransmitters is also a hormone which can be released into the blood stream to stimulate fight or flight responses?

Epinephrine

Which muscles lie deep to the rhomboid major and minor muscles?

Erector spinae

What is an important characteristic of fascicles in producing muscle contractions?

Fascicles allow for the change in direction of pull.

Which type of muscle fiber fatigues the quickest?

Fast glycolytic

Which types of muscle fibers use anaerobic energy systems for their primary source of ATP?

Fast glycolytic

Which muscle is located in the lateral compartment of the leg?

Fibularis longus

Simultaneous bilateral contraction of both sternocleidomastoid muscles results in this movement of the neck.

Flexion or extension

Which muscle is located in the anterior antebrachium?

Flexor carpi radialis

Which best describes the boundaries of a sarcomere?

From Z line to Z line

Which of the following is the primary inhibitory neurotransmitter in the nervous system?

GABA

Which muscle is located in the posterior sural region of the leg?

Gastrocnemius Correct

Which is not true regarding intercalated discs?

Help with anaerobic metabolism of ATP

What is the primary function of a desmosome?

Helps to keep cardiac muscle from separating during contraction

Which is not a function of smooth muscle in organs?

Helps to maintain erect posture

A student has tightness of her right piriformis muscle. What would be a valid observation of her lower extremities?

Her right foot would be turned out (laterally rotated)

Which best describes the motion of the iliopsoas group of muscles?

Hip flexion and lateral rotation

The effect of GABA stimulation on a postsynaptic neuron will likely produce which of the following effects?

IPSP

How are fascicles arranged in pennate muscles?

In a feather-like arrangement

Which is not true regarding human growth hormone as a performance enhancing substance?

Increases the rest required after exercise

Which best describes a fascicle?

Individual bundle of muscle fibers

What is another name for a sensory neuron?

Input neuron

Which type of neuron is responsible for the initial conscious perception of hot water in a shower?

Interneuron

Which type of muscle contraction is characterized by the length of a muscle remaining the same?

Isometric

Which is true of treppe?

It can only be maintained with adequate ATP

What can we tell about the subscapularis muscle from its Latin root?

It is below another structure.

Which muscle works to open the mouth?

Lateral pterygoid

You hold a pen in front of a student and move the pen side to side. You notice that one eye cannot follow the pen laterally away from the nose. Which extrinsic eye muscle may be involved?

Lateral rectus

Which muscle attaches to the humerus?

Latissimus dorsi

Which of the following is responsible for causing muscle fibers to contract when removing a hand from hot water in a shower?

Lower motor neuron

During a bicep curl, which is the eccentric phase of the exercise?

Lowering the weight by extending the elbow

Which glial cells attack microbes and removes debris?

Microglia

Which of the following neurons has an axon and multiple dendrites?

Multipolar neuron

Which type of neuron is considered the primary (or lower) motor neuron?

Multipolar neuron

Which best describes excitation-contraction coupling

Muscle fiber is stimulated, and then actin binds with myosin.

Which is characteristic of isotonic contractions?

Muscle length varies while load remains the same

Gray matter in the nervous system is devoid of what relative to white matter?

Myelin

Which of the following is the primary reason for the difference in appearance between gray and white matter?

Myelin

Why do slow oxidative fibers contain myoglobin?

Myoglobin carries oxygen needed for aerobic metabolism.

Where are the scalene muscles located?

Neck

Which of the following tissues contains cells which axons use to communicate?

Nervous

Which muscle works to furrow the brow?

Occipitofrontalis

Which cells produces myelin in the central nervous system (CNS)?

Oligodendrocytes

Which muscle is part of the femoral triangle?

Pectineus

Which muscle is located on the superior portion of the anterior thorax?

Pectoralis major

Which best describes the sarcolemma?

Plasma membrane surrounding a muscle fiber

Which ion primarily dictates repolarization involved in hyperpolarizing the membrane potential from -70mV to -90mV?

Potassium

Which is not a criterion for naming skeletal muscles?

Proximity to organs

Which abdominal muscle is enclosed by the linea alba?

Rectus abdominus

Which abdominal muscle would be considered the prime mover in performing an abdominal sit-up?

Rectus abdominus

Which is the longest phase of a muscle twitch?

Relaxation

What is the structure in muscle tissue that stores and releases calcium?

Sarcoplasmic reticulum

Which is not part of the quadriceps group of muscles?

Sartorius

Which muscle moves the thigh diagonally up and outward?

Sartorius

Which is a peripheral glial cell with similar supportive function as the astrocyte?

Satellite cell

These cells are located within skeletal muscle tissue and promote protein synthesis for growth and repair.

Satellite cells

Which is a true statement about fibrosis?

Scar tissue cannot produce the same amount of power as muscle tissue

Which cells produce myelin in the peripheral nervous system (PNS)

Schwan cells

Which type of neuron is responsible for processing initial input involved in detection of hot water in a shower?

Sensory neuron

Which muscle tissue has the greatest regeneration ability?

Smooth

Which is not true regarding the differences between smooth muscle and skeletal muscle?

Smooth muscle fibers have a much larger diameter

Which ion is primarily responsible for the change in membrane potential from -55mV to +30mV?

Sodium

Which system is specifically responsible for controlling skeletal muscle?

Somatic nervous system

Which is the major muscle that laterally flexes and rotates the head?

Sternocleidomastoid

Which best describes wave summation in muscle fibers?

Stimulation during twitch, causing stronger contraction

Which tongue muscle works to move the tongue in an upward and backward motion?

Styloglossus

Which rotator cuff muscle produces medial rotation of the humerus?

Subscapularis

Which is the most superior muscle associated with the rotator cuff?

Supraspinatus

Which of the following is the most distal (or terminal) part of a typical neuron?

Synaptic bulb

A friend frequently complains of headaches on the sides of her scalp. Which muscle could be contributing to her symptoms?

Temporalis

Which muscle is located on the lateral aspect of the thigh?

Tensor fascia latae

Which muscle is not a lateral rotator of the hip/thigh?

Tensor fascia latae

Which is true regarding the sarcomere during the sliding filament model?

The I Bands get smaller

Which of the following promotes depolarization of the muscle fiber?

The influx of sodium ions

Botox works by preventing the release of acetylcholine by motor neurons. How would this affect muscle fibers?

The motor end plate would not be able to depolarize Correct

What must first happen in order for excitation-contraction coupling to occur?

The nervous system must stimulate the muscle.

Which of the following typically occurs during depolarization?

The voltage moves closer to zero

Which is true about action potentials during the absolute refractory period?

They do not occur during the absolute period.

Which best describes the function of the internal intercostal muscles?

They draw ribs together during expiration.

Why are the quadriceps muscles considered antagonists in knee flexion?

They oppose the action of the hamstrings.

Which muscle raises the sole of the foot off of the ground?

Tibialis anterior

Which muscle forms the deepest layer of abdominal muscles?

Transversus abdominus

Which muscle is involved in shrugging the shoulders?

Trapezius

Which muscle is not part of the erector spinae group?

Trapezius

Which muscle is located on the posterior portion of the arm?

Triceps brachii

Where does calcium bind in the muscle cell to promote contraction?

Troponin

In which type of muscle are fascicles arranged on one side of a tendon running alongside the muscle?

Unipennate

Which of the following is considered the primary sensory neuron?

Unipolar neuron

Which event occurs during repolarization?

Voltage-gated K+ channels open

Which event predominantly dictates the repolarization phase of a neuronal action potential?

Voltage-gated K+ channels open

Which of the following contains myelinated axons?

White matter

Which best describes an agonist muscle?

Works to produce movements

Actin and myosin are arranged in regular patterns in ____ muscle tissue.

cardiac and skeletal

Depolarization of the postsynaptic membrane by a neurotransmitter is considered:

excitatory. Correct

A sprinter would specifically want to train____ fibers while a marathoner would train ____ fibers?

fast glycolytic; slow oxidative

Dendrites are usually

highly branched.

Hyperpolarization of the postsynaptic membrane by a neurotransmitter is considered

inhibitory.

The H zone of the sarcomere contains

myosin only

A bundle of myelinated axons in the peripheral nervous system (PNS) is referred to as a

nerve

A group of neuron cell bodies in the central nervous system (CNS) is referred to as a

nucleus.

Some tendons attach to the mysia of muscles on one end and the ____ of bone on the other.

periosteum

Diffusion, enzymatic degradation, and uptake by cells are all ways to

remove a neurotransmitter.

When a cell becomes stimulated (excited)

sodium gates in the cell membrane open.

The peripheral nervous system is comprised of

spinal nerves.

Regarding the rectus abdominus muscle, the root "rectus" means _____.

straight

In the foot, the dorsal group consists of ____layer(s) of muscles.

three

A bundle of myelinated axons in the central nervous system (CNS) is referred to as a

tract.