bio 201 exam 3

The plexus that travels through the axillary region is the

Brachial

The central nervous system or CNS of vertebrate animals consists of

Brain and Spinal cord

A given neurotransmitter can produce either excitatory or inhibitory effects on postsynaptic neurons depending on the specific receptor type it binds.

True

Which of the following is NOT a neurotransmitter

atropine

Which of the following does NOT increase the strength of contraction?

availability of iron

which of the following does not increase the strength of a contraction

availability of iron

Which of the following is NOT a spinal cord region

axial

Which nerve supplies muscles of the rotator cuff?

axillary

Which part of the neuron is responsible for propagating action potentials?

axon

When a resting muscle is stimulated, its electrical potential:

becomes more positive

This plexus is formed by the ventral rami of nerves C4 to T2. It innervates the upper limb and some muscles of the neck and shoulder.

brachial

A ganglion is a

bundle of axons in the CNS

The epineurium

bundles fascicles into nerves

All of the following events occur when a nerve signal reaches a synaptic knob. The one that occurs first is

calcium ions enter the synaptic knob

The sarcoplasmic reticulum stores ____ ions and forms dilated sacs alongside transverse (T) tubules called the _____.

calcium; terminal cisternae

why is blockage of a coronary artery such a serious threat to cardiac muscle

cardiocytes have abundant mitochondria and rely on a constant supply of oxygen

quadriplegia would result if the spinal cord was severed at

C2

All of the following statements about initiation and transmission of action potentials in neurons are correct EXCEPT:

Information about the intensity of a stimulus is conveyed by changes in the size of the action potential generated.

The nerves projecting inferiorly from the spinal cord are collectively called the

cauda equina

A threshold stimulus applied to an excitable membrane is one that is just sufficient to cause a change in membrane potential depolarize a dendrite be conducted to the axon hillock cause a net inward movement of positive charge through the membrane

cause a net inward movement of positive charge through the membrane

A reflex arc in which both the receptor and effector organs of the reflex are on the same side of the spinal cord is

Ipsilateral

During an isometric contraction of a skeletal muscle

Isometric contractions involve sarcomere shortening and increasing muscle tension, but do not move a load, as the force produced cannot overcome the resistance provided by the load

Identify the statement concerning skeletal muscle that is true.

It is responsible for locomotion.

Which of the following is an autoimmune disease in which antibodies attack the neuromuscular junctions and bind Ach receptors together in clusters?

Myasthenia Gravis

A nerve impulse travels fastest along ________ axons of ______ diameter.

Myelinated; large

During the rising phase of an action potential, voltage-gated

Na+ channels open

This viral infestation can remain viable with the dorsal root ganglia for many years.

chickenpox

Which does not cause smooth muscle contraction

collagen

T tubules

conduct action potentials deep into the muscle cell.

Which of the following is NOT part of the thin filaments of striated muscle?

connectin

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

constriction of organs

lack of acetylcholinesterase in the synaptic cleft would result in

continuous stimulation of postsynaptic membrane

Lack of acetylcholinesterase in the synaptic cleft would result in

continuous stimulation of the post-synaptic membrane

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

contractility

If sodium ions cannot enter a muscle fiber in response to a stimulus,

contraction cannot occur

In comparison to skeletal muscle, smooth muscle

contracts and relaxes more slowly

If the origin of a motor signal is the left side of the brain, but the destination of that signal is the right hand, we say that the spinal tract relaying the information is

contralateral

Nissl bodies are ________ and are located in the __________ of a neuron

endoplasmic reticulum; soma

The glial cell that helps to form cerebrospinal fluid is the

ependymal cell

Anesthetics and anti-inflammatory drugs are introduced into this space in the vertebral column.

epidural

action potential transmission in the PNS is decreased if which cells are damaged?

Schwann Cells

Remembering the three things that you need to pick up at the grocery store on your way home is an example of

Short-term memory

The type of muscle fibers that have only a single nucleus, both thick and thin filaments, but no Z discs

Smooth

Which of the following statements is FALSE?

Smooth muscle does not have actin & myosin.

___ nerve fibers are those that innervate the skin and skeletal muscles.

Somatic

A muscle whose name has "superficialis" in it is located On the front Parallel to the midline Superficially Deep On the side

Superficially

At the distal end of a nerve fiber, action potentials have the same voltage as they had at the beginning. This means that they are

nondecremental

lumborum means ____ while brachii means _____

of the lower back; of the arm

The glial cell that helps to form the myelin sheath in the CNS is the

oligodendrocyte

A sarcomere extends from

one Z disk to an adjacent Z disk

Which of these happens first in an cholinergic synaptic transmission?

Synaptic vesicles release ACh

Endurance is determind by the supply of

oxygen, glucose, fatty acids, amino acids (all of the above)

__________ are straplike muscles of uniform width whose fascicles all fun in the same direction

parallel muscles

The spinal cord is divided into all of the following regions except

pelvic

The connective tissue wrapping that surronds bundles (fascicles) of axons is the

perineurium

The connective tissue wrapping that surrounds bundles (fascicles) of axons is the

perineurium

A neuron innervating your bicep muscle would be considered part of the

peripheral nervous system

A neuron innervating your bicep muscle would be consisdered part of the

peripheral nervous system

From deep to superficial, the meninges occur in the order

pia mater, arachnoid, dura mater

The bladder's ability to greatly distend and return to normal tension is due to the ___ of smooth muscles.

plasticity

Which is NOT a universal characteristic of all muscles?

plasticity

Which of the following is NOT a characteristic of a muscle cell?

plasticity

Which of the following disease of the central nervous system can be prevented by a vaccine?

poliomyelitis

The phenomemon of __________ enables frequently used synapses to transmit signals more easily in long-term memory

post-tetanic potentiation

The phenomenon of __________ enbables frequently used synapses to transmit signals more easily in long-term memory

post-tetanic potentiation

the adaptive significance of the crossed extensor reflex when a person steps on a tack is to

prevent the person from falling down

A muscle which does most of the work during a specific action is called the

prime mover

After contraction has occured, the calcium is

released from troponin.

The charge difference across the plasma membrane in relaxed muscles and nerve cells is called the ______ .

resting potential

Stiffening of the body following death is called

rigor mortis

The plexus formed from the anterior rami of L4-S4 is the __________ plexus

sacral

T tubules are extensions of the ______________ in skeletal muscle.

sarcolemma

The contractile unit of a muscle fiber is called a

sarcomere

The functional unit of a skeletal muscle fiber is the

sarcomere

The distance from one Z disc to the next is called the ________ and it __________ during contraction

sarcomere; shortens

In skeletal muscle fibers, a network of calcium storage sacs is called

sarcoplasmic reticulum

what structure stores calcium ions that trigger contraction

sarcoplasmic reticulum

Which of the following is mismatched?

schwann cells- secrete nerve growth factors

The largest and longest nerve in the body is the _________ nerve.

sciatic

When a person sits on a hard surface for a period of time, his foot or leg may "go to sleep." This sensation is the result of compressing the _____ nerve.

sciatic

The afferent division of the nervous system is also known as the _____ division.

sensory

The peripheral nervous system includes the

sensory nerves and motor nerves

each of the following terms is a descriptive term for a muscle's action except

serratus

Which of the following characteristics would establish conclusively that muscle tissue being examined was skeletal muscle tissue?

several nuclei per cell

Which type of muscle has fibers as long as 30cm?

skeletal

Which of the following is voluntary muscle?

skeletal muscle

Which of the following is NOT an example of procedural long term memory

skiing

The type of fibers specialized to continue contracting for extended periods of time, as would be required in running a marathon, for example, are ________ fibers

slow

Posture is maintained mainly by _____ fibers.

slow oxidative (SO)

Which muscle(s) can contract without the need for nervous stimulation?

smooth and cardiac muscle

gap junctions are characteristic of

smooth muscle

Identify the incorrect statement

smooth muscle is voluntary

In resting muscle or nerve cell, there are excess _______ ions in the extracellular fluid and excess ________ ions in the intracelluar fluid

sodium; potassium

Exposure to Clostridium tetani causes continuous release of ach. What effect does this have on skeletal muscle? myocardial atrophy spastic paralyis treppe flaccid paralysis

spastic paralysis

which does not belong to the peripheral nervous system

spinal cord

which does not belong to the peripheral nervous system?

spinal cord

In a lumbar puncture (spinal tap), fluid is extracted from the

subarachnoid space

The majority of cerebrospinal fluid in the spinal cord is found in the

subarachnoid space.

All of these contribute to the cessation of the signal in a synaptic transmission except

synaptic vesicles secrete neurotransmitter by exocytosis

Muscles that work together to cause movement are called insertions antagonists origins prime movers (wrong) synergists

synergists

The region of a sarcomere where actin and myosin overlap is

the A band

Action potentials are propagated from the surface to the interior of a muscle fiber by way of

the T tubules

In order for muscle relaxation to occur,

the active sites on actin must be blocked.

To treat some of the symptoms of Myasthenia gravis, physicians sometimes prescribe the anticholinesterase drug neostigmine. Why does this drug help with the symptoms of muscle weakness and fatigue?

The drug inhibits the activity of acetylcholinesterase, which prevents the breakdown of ACh. Consequently, ACh levels in the synapse remain elevated, thereby increasing the stimulation of the reduced number of functional ACh receptors.

Which of these spinal nerve counts is incorrect?

Thoracic nerves = 8 pairs

Which is not a function of the motor division of the nervous system?

Transmits impulses from the viscera

Arrange the following list of biochemical events in the correct sequence. (1) An action potential is conducted deep into the muscle fiber by the T tubule. (2) Calcium ions bind to troponin. (3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions. (4) Calcium ions diffuse into the sarcoplasm around the myofibril. (5) The troponin-tropomyosin complex moves exposing active sites.

(1) An action potential is conducted deep into the muscle fiber by the T tubule (3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions. (4) Calcium ions diffuse into the sarcoplasm around the myofibril. (2) Calcium ions bind to troponin. (5) The troponin-tropomyosin complex moves exposing active sites.

The resting potential across a sarcolemma of a skeletal muscle cell is about _______ millivolts (mV)

-90

One muscle fiber is stimulated by how many somatic motor neurons?

1

Due to overlap of dermatomes, a total loss of sensation requires anesthesia of _________ successive spinal nerves?

3

Put the following events in chronological order. (1) Ca++ floods into the pre-synaptic neuron. (2) Ach (Acetylcholine) binds to ACh receptors in the sarcolemma. (3) Na+ floods into the post-synaptic muscle cell. (4) The action potential arrives at the pre-synaptic terminal causing Ca++ channels to open. (5) Ach from the synaptic vesicles spills into the pre-synaptic cleft. (6) A post-synaptic action potential results in the muscle fiber (depolarization).

4, 1, 5, 2, 3, 6

Arrange the events of synaptic transmission in correct sequence. (1) Na+ diffuses into the cell and cause a local potential (2) Neurotransmitter binds with receptor on postsynaptic cell (3) Neurotransmitter diffuses across the synaptic cleft (4) Membrane permeability to Na+ on postsynaptic cell increases (5) Action potential causes release of neurotransmitter

5, 3, 2, 4, 1

Action potentials would be conducted most rapidly by all action potentials are conducted at the same rate. a 5 mm diameter unmyelinated axon. a 5 mm diameter myelinated axon. a 55 mm diameter unmyelinated axon. a 55 mm diameter myelinated axon

55 mm diameter myelinated axon (large myelinated are fastest)

Which of the following fractures would be the least likely to cause a spinal cord injury

A fracture of vertebra L4

Choose the answer that correctly lists, in chronological order, the events involved in synaptic transmission: A: a nerve impulse reaches the synaptic knob B: Neurotransmitter molecules diffuse across the synaptic cleft C: A nerve impulse begins in the postsynaptic cell D: Neurotransmitter molecules bind to receptors in the postsynaptic cell E: A voltage change occurs in the postsynaptic cell

A: a nerve impulse reaches the synaptic knob B: Neurotransmitter molecules diffuse across the synaptic cleft D: Neurotransmitter molecules bind to receptors in the postsynaptic cell E: A voltage change occurs in the postsynaptic cell C: A nerve impulse begins in the postsynaptic cell

________ is required for muscle relaxation

ATP

Which of the following is not found in the thin filaments of striated muscle? F actin ATPase troponin Ca2+ receptors

ATPase

Which ions are important for establishing the resting potential in neurons?

All of the choices other than H+ are correct (Na, K, intracellular anions)

Which of the following statements best describes the membrane situation in the resting state of the neuron?

All of the voltage-gated Na and K channels are closed

Aerobic exercise develops fatigue-resistant fast-twitch fibers. increases vascularity of muscle. All of these choices are correct. can increase the number of mitochondria in muscle cells. can increase the efficiency of slow-twitch fibers

All of these choices are correct.

Which of the following statements is FALSE?

At rest, the concentration of Na+ is higher inside the cell than outside

The plexus that supplies the upper limbs is the _________ plexus.

Brachial

Rising intracellular levels of which ion are necessary for neurotransmitter release from a neuron?

Ca2+

The type of muscle fibers that are striated, form Y-shaped branches, and have junctions called intercalated discs are

Cardiac

What is the correct order for the parts of the spinal cord, from superior to inferior?

Cervical - thoracic - lumbar - sacral - coccygeal

There are two types of synapses, based on mode of communication. What are they?

Chemical and Electrical

A reflex arc in which the receptor and effector organs of the reflex are on the opposite side of the spinal cord is

Contralateral

____ are the primary site for receiving signals from other neurons.

Dendrites

___ carry motor commands from the brain along the spinal cord.

Descending tracts

_______ carry motor commands from the brain along the spinal cord

Descending tracts

___ keep(s) nerve fibers insulated from one another.

Endoneurium

Which of the following is true about skeletal muscle?

Every muscle fiber receives a branch of an axon from the nerve.

A neurotransmitter that was inhibitory would produce an ______ that would ____ a neuron.

IPSP, hyperpolarize

Which of the following is true?

In saltatory conduction, electrical charges jump from node to node

Curare is a poison used by south american indians. It is known to bind to ACh receptors preventing the binding of ACh. What effect would it have on muscle function?

The muscle fibers would not contract because the Na+ channels which cause depolarization of the muscle fiber membrane are never signaled to open

When comparing smooth and skeletal muscle cells, which of the following statements is true?

The myofilaments in smooth muscle do not form sarcomeres.

____ division carries signals to the smooth muscle in the large intestine.

Visceral motor

The gangster movies call a dead person a stiff, rigor mortis is the proper name. How does this occur?

Without ATP, muscles remain fixed in their last state of contraction.

Which of these processes occurs during the contraction of skeletal muscle

Z discs move closer together

Which of the follwoing individuals would have more mitochondria in his skeletal muscle

a 22 year old football player

Which are the locations of neuron cell bodies? a: peripheral ganglia b: gray matter c: white matter d: meninges e: central canal of spinal cord

a and b

which of the following is an effector?

a gland

In contrast to skeletal muscle, smooth muscle has all of the following properties except

a more extensive sarcoplasmic reticulum

Choose the answer that correctly lists, in chronological order, the events involved in synaptic transmission. a: A nerve impulse reaches the synaptic knob b: Neurotransmitter molecules diffuse across the synaptic cleft c: A nerve impulse begins in the postsynaptic cell d: Neurotransmitter molecules bind to receptors in the postsynaptic cell e: A voltage change occurs in the postsynaptic cell

a, b, d, e, c

Which is the correct order of the connective tissue layers of a skeletal muscle, beginning with the innermost first? a: endomysium b: epimysium c: perimysium

a, c, b

Which are considered specific functions of the spinal cord? a: conductivity b: extensibility c: locomotion d: emotion e: reflexes

a, c, e

Which is a correct listing of the hierarchy of a skeletal muscle's components beginning with the smallest? a: myofibrils b: muscle fiber c: fascicle d: skeletal muscle

a,b,c,d

which is the correct order of the connective tissue layers of a skeletal muscle, beginning with the innermost first? a:endomysium b:epimysium c:perimysium

a,c,b

___________ is a neurotransmitter that triggers muscle contraction

acetylcholine

In the neuromuscular junction, ACh released into the synaptic cleft is rapidly destroyed by

acetylcholinesterase

Which protein makes up the thin filaments?

actin

During the contraction phase of a muscle twitch,

actin-myosin cross-bridges form

Cross-bridges form between _______ and ________ during muscular contraction

actin; myosin

The epidural space in the spinal column is occupied by

adipose tissue

_________ neurons are specialized to detect stimuli, whereas ___________ send signals to the effectors of the nervous system

afferent; efferent

endurance is determined by the supply of

all of the above

The straiations observed in skeletal and cardiac muscles are produced by

alternating A bands and I bands

Nerve fiber refers to

an axon

A long-distance runner asks her coach why it is so difficult to have a "finishing kick" (sprinting the last hundred yards to the finish line) Her coach should reply

anaerobic activities like sprinting are limitied by available glucose and rate of buildup of lactic acid

The biceps brachii muscle and the triceps brachii muscle

are antagonists

smooth muscles

are innervated by somatic nerve fibers only

calcium ions

are released from the T tubules by active transport

A condition known as flaccid paralysis

arises because the muscle is incapable of contracting in response to nervous stimulation

When there is not enough oxygen to create ATP by aerobic respiration, a muscle fiber can produce ATP by borrowing phosphate groups from

creatine phosphate

when there is not enough oxygen to create ATP by aerobic respiration, a muscle fiber can produce ATP by borrowing phosphate groups from

creatine phosphate

Sarcoplasm is the

cytoplasm of muscle cells

The posterior ramus of a typical spinal nerve innervates the

deep muscles of the back and the skin of the back

In a neuron, __________ receive signals from sensory receptors

dendrites

In a neuron, __________ receive signals from sensory receptors.

dendrites

The effect of increasing the flow of Na+ ions into a neuron at rest (-70 mV initially) would be termed

depolarization

****An increase in the extracellular concentration of K+ above normal would result in (not 100% sure)

depolarization of resting nerve cells

Opening of sodium gates typically leads to

depolarization of the plasma membrane

The cutaneous regions innervated by specific spinal nerves are each called a

dermatome

The cutaneous sensory distribution of a spinal nerve can be mapped as a

dermatome

Damage to the phrenic nerve would result in

difficulty breathing

A deficiency of ACh receptors in a motor endplate would cause ____ and is called _____.

difficulty firing muscle fibers; myasthenia gravis

Parkinson disease is a progressive loss of motor function due to the degeneration of specific neurons. These neurons secrete an inhibitory neurotransmitter that prevents excessive activity in motor centers of the brain. This neurotransmitter is

dopamine

The thicket of the meninges is the

dura mater

From superficial to deep, the meninges occur in the order

dura mater, arachnoid, pia mater

Motor nerves are known as_________ nerves and sensory nerves are known as _________ nerves

efferent; afferent

There are ________ cervical spinal nerves.

eight

The ability of the muscle cell to return to its initial length after being stretched is

elasticity

Which is a connective tissue sheath that surrounds an individual muscle fiber?

endomysium

You were going to have a spinal tap to remove some cerebrospinal fluid for analysis. Starting from outside of the spinal cord, what would be the correct order of spaces and meninges through which the syringe would pass?

epidural space, dura mater, arachnoid mater, subarachnoid space

Which of the follwoing would occupy lumen of a transverese tubule

extracellular fluid

_______ are examples of muscles under fine motor control

eye muscles

Gray matter tracts of the spinal cord carry sensory information up to the brain and motor information down from the brain

false

Regeneration of axons occurs more readily in the CNS that in the PNS

false

The fat and connective tissue that enciricle a beef steak from the endomysium

false

In skeletal muscle, Indiviudal muscle cells are called _______ and are surrounded by a connective tissue sheath called the _____

fascicles, endomysium

In skeletal muscle, groups of muscle cells are called _______ and are surrounded by a connective tissue sheath called the _____

fascicles, perimysium (this is right!!)

You would expect a body-builder to have more __________ muscle fiber than a long-distance marathon runner

fast glycolytic

The movement of your fingers is controlled by muscles which have a greater proportion of

fast glycolytic fibers with small motor units

The names of the muscles can indicate all of the following except

fat content of the muscle

In contrast to red muscle fibers, white fibers

fatigue more quickly

The thin strand of pia mater that helps to anchor the spinal cord to the coccyx is the

filum terminale

Which of the following describes an appearance of red muscular tissue emerging directly from bone rather than being separated from it by an obvious tendon?

fleshy attachment

A nurse pricks your finger to type your blood. You flinch at the pain, pulling your hand back. This is called the

flexor (withdrawal) reflex

___________ are muscles which are widest in the middle and then taper at the ends

fusiform muscles

Outside the CNS, groups of neuronal cell bodies that are clustered together to perform basic functions are termed

ganglia.

In cardiac muscle and single-unit smooth muscle, ions can flow directly from one cell into an adjacent cell through

gap junctions

A brief activity using maximum muscular effort (weight-lifting) is commonly fueled by the

glycogen-lactic acid system (anaerobic)

Local potentials are _______, meaning they vary in magnitude according to the strength of the stimulus

graded

Slow-twitch muscle fibers

have a richer blood supply than fast twitch fibers, and contain myoglobin

Which cellular organelle is not functioning properly in order to allow for the accumulation of a glycolipid in the myelin sheath of those with Tay-Sach's disease?

lysosomes

Shivering

helps raise body temperature

shivering

helps raise body temperature

Inhibitory postsynaptic potentials (IPSPs) are associated with

hyperpolarization of the cell membrane

which of the following would NOT contribute to muscular fatigue in the fiber?

increased level of serotonin

Which of the following would not contribute to muscular fatigue in the muscle fiber? blocked receptors in the postsynaptic membrane increased levels of serotonin the inability of the motor neuron to produce sufficient quantities of ach depletion of neurotransmitter

increased levels of serotonin

Which of the following would you expect to find in skeletal muscle cells of endurance trained athletes?

increased number of mitochondria

A neurotransmitter, such as glycine, attaches to a receptor and causes hyperpolarization. This neurotransmitter would most likely cause an

inhibitory local potential

The _______ of a muscle is located on the bone that moves

insertion

several genetic disorders including Tay Sach's disease strip in the myelin sheath from nerve cells. The myelin sheath serves to ____ the axon

insulate

Muscle tone

is a constant tension produced by muscles

Which contraction occurs when you try (unsuccessfully) to move a wall?

isometric

When a muscle develops increased tension, but does not change in length, it is said to exhibit

isometric contraction.

Conduction speed of a nerve fiber would be the fastest in a

large myelinated fiber

A volleyball player depends on the gastrocnemius muscles for plantar flexion, whereas a marathon runner depends more on the soleus muscles for the same reaction. This is because the soleus muscles

make more use of aerobic respiration

A synergist

may stabilize a joint or modify direction of movement at the joint

which of the following is NOT an example of procedural long term memory

moderate

The efferent division of the nervous system is also known as the _____ division.

motor

The neurons that stimulate muscle contraction are called ________ neurons

motor

A depression in a muscle fiber where it has synaptic contact with a nerve fiber and a high density of neurotransmitter receptors is a

motor endplate

A motor neuron and the muscle fibers it innevates is called a

motor unit

If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of

movement

which of the following is not primarily associated with skeletal muscle

moving contents through the digestive tract

The disease ______________ is characterized by destruction of CNS myelin sheaths and the formation of hardened scars.

multiple sclerosis

This condition involves progressive demyelination of neurons in the CNS accompanied by the destruction of oligodendrocytes. Ad a result, the conduction of nerve impulses is disrupted, leading to impaired sensory perception and motor coordination

multiple sclerosis

The brachial plexus supplies nerves that function to contract which of the following?

muscles of the arm and forearm

A 35 year old woman complains of drooping eyelids, weakness in her limbs and poor physical endurance. What is a likely cause of her symptoms

myasthenia gravis

White matter is

myelinated axons in the CNS

From largest to smallest, which of the following is the correct order?

myofilament, myofibril, myofiber

The bright red color of skeletal muscle is due mainly to its

myoglobin

Slow oxidative (SO) fibers (slow-twitch fibers) have more ________ and less _________ than fast glycolytic (FG) fibers (fast twitch fibers)

myoglobin, lactic acid

slow oxidative (SO) fibers (slow twitch fibers) have more _____ and less ______ than fast glycolytic (FG) fibers (fast twitch fibers)

myoglobin, lactic acid

which of the following is the correct sequence of events in cross bridge cycling

myosin cross-bridge binds to actin, the powerstroke moves the thin filament relative to the thick filament, ATP binds to myosin and cross-bridge detatchment occurs, ATP is hydrolyzed and the myosin head is "cocked"

Nervous tissue consists mainly of what two major types of cells?

neuroglial cells and neurons

Barry asked his physician why tentanus shots were necessary. The doctor explained that ______

the bacterium Clostridium tetani can cause the muscles to tentay and stay contracted causing death

the burning sensation that you feel in your muscles when you are lifting weights is presumably caused by

the build-up of lactic acid

Otto Loewi performed an experiment in which he electrically stimulated the vagus nerve connected to one frog heart and let the fluid bathing his first heart pass to a second chamber containing second frog hear not connected to a nerve. What did Loewi observe?

the first heart showed a decrease in beat rate and so did the second heart

when comparing smooth and skeletal muscle cells, which of the following statements is true?

the myofilaments in smooth muscle do not form sarcomeres

The right brachial plexus primarily supplies

the right arm

Synaptic vesicles are found in

the synaptic knob

A neuron fires only when its membrane reaches

the threshold potential

Nerve fibers that stimulate the skeletal muscles of your foot have their somas in

the ventral horn of the spinal cord.

Local potentials exhibit all of the following charchteristics except

they obey the all or none law

Which of the following is composed of myosin molecules?

thick myofilaments

In which body region would you expect to find a muscle whose name included the word "pollicis" ?

thumb

Which of the following is not a purpose of the excess postexercise oxygen consumption (EPOC) in muscle?

to neutralize carbon dioxide buildup

a threshold stimulus applied to an excitable membrane is one that is just sufficient to

trigger an action potential

When calcium ions are released from the sarcoplasmic reticulum, they combine with the protein ______

troponin

Which of the following would occur as a result of a single muscle contraction

twitch

There are _____ enlargements of the spinal cord where nerves supplying the extremities enter and leave.

two

You are examining a cross-sectional slide of a muscle, and you noticed the following characteristics in most of the muscle fibers: smaller diameter, abundant mitochondria and myoglobin, and low levels of gylcogen reserves. This muscle is predominantly made up of fibers that are

type 1 and slow oxidative

you are examining a cross-sectional slide of a muscle, and you noticed the following characteristics in most of the muscle fibers: smaller diameter, abundant mitochondria, abundant myoglobin, and low levels of glycogen reserves. This muscle is predominantly made up of fibers that

type I and slow oxidative

The motor root of a spinal nerve is also referred to as the

ventral root.

Which of the following does NOT apply to cardiac muscle?

voluntary

Stepping on a piece of glass would most likely invoke a _____ reflex.

withdrawal