Review practice quiz for EXAM 3 A&P

The dense layer of connective tissue that surrounds an entire skeletal muscle is the

epimysium

Capillaries, nerves, and myosatellite cells are located in the

endomysium

The plasma membrane of a skeletal muscle fiber is called the 

sarcolemma

Stem cells that function in the repair of damaged skeletal muscle tissue are called

myosatellite cells

When a skeletal muscle fiber contracts, the

zones of overlap get larger

The action potential is conducted into the interior of a skeletal muscle fiber by

transverse tubules

Active sites on the actin filament become available for binding after

calcium binds to troponin.

Each skeletal muscle fiber is controlled by a motor neuron at a single

neuromuscular junction

A patient takes a medication that blocks ACh receptors of skeletal muscle fibers. What is this drug's effect on skeletal muscle contraction?

reduces the muscle’s ability for contraction

The addition of one twitch to another, each stronger than the last, as shown in graph b is called 

wave summation

The type of muscle fiber that is most resistant to fatigue is the ________ fiber

slow oxidative

When calcium ions enter smooth muscle cells to initiate contraction, which of the following best describes the next step in the process?

Calcium binds to calmodulin, which then activates myosin light chain kinase to phosphorylate myosin.

Both cardiac muscle and certain types of smooth muscle exhibit automaticity. Which of the following best describes this characteristic?

The ability of the muscle cells to depolarize and trigger a contraction independently of the nervous system.

Which of the following is a recognized function of skeletal muscle?

all answers are correct

At the end of the muscle, the collage fibers of the epimysium, perimysium, and endomysium come together to form a

tendon

When the sarcomere shortens

z lines move closer together

At rest, active sites on the actin filament are blocked by

tropomyosin molecules

A single contraction-relaxation cycle in a muscle fiber produces a(n)

twitch

A muscle produces its highest tension when in complete

tetanus

Aerobic metabolism normally provides ________percent of the ATP demands of a resting muscle cell

95

Large-diameter, densely packed myofibrils, large glycogen reserves, and few mitochondria are characteristics of 

fast (fast glycolytic) fibers

Which of the following features is unique to cardiac muscle and distinguishes it from skeletal muscle?

The presence of intercalated discs containing gap junctions that allow the cells to contract together as a single coordinated unit. 

Muscles that guard entrances and exits of internal passageways are____________muscles

circular

Most of the skeletal muscles in the body are ___________muscles. 

parallel

The end of a muscle that remains stationary when the muscle contracts is called the _________

origin

Muscles visible at the body surface are often called ________________

superficialis

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

sartorius

Which of the following muscles compresses the abdomen?

transverse abdominis

The muscle which covers the anterior surface of the neck is called the

platysma

Which muscle is indicated by the arrow?

sartorius

Which of these muscles is indicated by the arrow?

biceps femoris

Which of these muscles is indicated by the arrow?

Deltoid

Sensory information travels to the CNS along ________ pathways.

afferent

Small, phagocytic cells in the CNS are

microglia

Regions with large concentrations of neuronal cell bodies and very little myelin are called ________ matter.

grey

_______________carry motor information to peripheral effectors. 

efferent neurons

The minimum stimulus required to trigger an action potential is known as the

threshold

The period during which an excitable membrane can respond again, but only if the stimulus is greater than the threshold stimulus, is the _________period. 

relative refractory

Saltatory propagation could be defined as moving

from node to node

The ion that triggers the release of acetylcholine into the synaptic cleft is

calcium

When a second EPSP (excitatory postsynaptic potential) arrives at a single synapse before the effects of the first have disappeared, what occurs?

temporal summation

The  most common class of neuron in the central nervous system is

multipolar

The fibers of a ___________muscle are arranged much like a feather

pennate

The more movable point of muscle attachment is called the 

insertion

Muscles located close to the midline of the body may be called

medialis

Terms which indicate the muscle is visible at the body's surface:

externus, superficialis

The structure labeled 4 in this picture of a neuron indicates the

telodendria

The ________ nervous system is composed of the brain and spinal cord.

central

_____________are the most numerous type of neuron in the CNS

interneurons

The site of intercellular communication between a neuron and another cell is the 

synapse

If the permeability of a resting axon to sodium ion increases

inward movement of sodium ion will increase

The neuroglial cells that participate in maintaining the blood-brain barrier are

astrocytes

What will happen if a resting neuron's membrane becomes more permeable to sodium?

sodium will enter the cell

the membrane will depolarize

A neuron that receives neurotransmitter from another neuron is called 

the postsynaptic neuron