Anatomy and Physiology: Muscular and Nervous Systems Comprehensive Review

A high-yield deck of 100 fill-in-the-blank practice flashcards covering skeletal muscle physiology, axial and appendicular musculature, nervous tissue, brain anatomy, spinal cord pathways and reflexes, the autonomic nervous system, and special senses.

Skeletal muscle fibers are histological characterized as striated, tubular, and __________ with multiple peripheral nuclei.

multinucleated

The property of muscle tissue that describes the ability to return to its original length following lengthening or shortening is known as __________.

elasticity

The outermost concentric connective tissue layer composed of dense irregular connective tissue that encloses an entire skeletal muscle is the __________.

epimysium

In skeletal muscle, a fascicle is enveloped by a layer of dense irregular connective tissue known as the __________.

perimysium

The delicate layer of areolar connective tissue that surrounds each individual skeletal muscle fiber is the __________.

endomysium

In a skeletal muscle fiber, a triad is formed by a centrally located transverse tubule (T-tubule) flanked by two terminal cisternae of the __________.

sarcoplasmic reticulum

Within a sarcomere, the light-appearing band containing exclusively thin filaments is termed the __________.

I band

The transverse protein structure located in the center of the H zone that serves as an attachment site for thick filaments is the __________.

M line

As shown in the graph of sarcolemmal action potential events, the resting membrane potential changes from $-90\,mV$ to the threshold value of __________ when sufficient $\text{Na}^+$ enters the motor end plate.

$$-65\,mV$$

During the power stroke of skeletal muscle crossbridge cycling, the myosin head swivels toward the center of the sarcomere, releasing ADP and __________.

$$\text{P}_i$$

The skeletal muscle fiber type characterized by small diameter, red color due to abundant myoglobin, and high fatigue resistance via aerobic respiration is the __________ fiber.

slow oxidative (SO)

In the phases of a muscle twitch shown in the chart, the delay occurring after stimulus arrival but before tension rises is designated the __________.

latent period

The type of isotonic contraction illustrated here, in which the muscle generates tension while lengthening, is classified as an __________ contraction.

eccentric

The specialized intercellular junctions that join adjacent cardiac muscle cells and contain both desmosomes and gap junctions are termed __________.

intercalated discs

In smooth muscle cells, intermediate filaments of the cytoskeleton link to points in the sarcoplasm called __________.

dense bodies

During excitation of smooth muscle, calcium binds to calmodulin, forming a complex that activates the enzyme __________ to phosphorylate myosin heads.

myosin light-chain kinase (MLCK)

The muscle division highlighted in the diagram that supports and moves the head and vertebral column and protects abdominal and pelvic organs comprises the __________ muscles.

axial

In appendicular skeletal muscles, the relatively fixed, less moveable attachment site is known as the __________ attachment.

proximal (origin)

The structural pattern of muscle fascicles shown in this illustration, where all fibers attach at an angle along one side of a tendon, is termed __________.

unipennate

A muscle whose contraction directly opposes that of the agonist to ensure controlled, smooth movement is called an __________.

antagonist

The superficial facial muscle demonstrated on the right side of this figure, which tenses the skin of the neck and pulls the lower lip inferiorly, is the __________.

platysma

The most powerful muscle of mastication, which elevates and protracts the mandible, is the __________.

masseter

The extrinsic eye muscle that loops through a pulley-shaped ligament called the trochlea to depress and turn the eye laterally is the __________ muscle.

superior oblique

The internally placed dome-shaped muscle illustrated here, which contracts during inspiration so its central tendon is pulled inferiorly, is the __________.

diaphragm

From lateral to medial, the three longitudinal muscle groups that form the erector spinae are the iliocostalis, longissimus, and __________ groups.

spinalis

The deepest muscle of the abdominal wall, whose fibers project in a horizontal/transverse orientation, is the __________.

transversus abdominis

Among the rotator cuff muscles (S.I.T.S.), the muscle responsible for initiating abduction of the arm at the glenohumeral joint is the __________.

supraspinatus

The anterior arm muscle situated deep to the biceps brachii that functions as a powerful flexor of the forearm at the elbow joint is the __________.

brachialis

The deep anterior forearm muscle that flexes the metacarpophalangeal and interphalangeal joints of the thumb is the __________.

flexor pollicis longus

In the posterior thigh compartment shown, the lateral hamstring muscle consisting of both a long head and a short head is the __________.

biceps femoris

The primary dorsiflexor of the foot located in the anterior leg compartment that also inverts the foot is the __________.

tibialis anterior

In the functional organization of the nervous system shown, sensory input received from blood vessels and internal organs is categorized as __________ sensory.

visceral

The tough outermost sheath of dense irregular connective tissue enclosing a peripheral nerve is the __________.

epineurium

Because mature neurons generally lose their capacity to undergo mitosis and form new cells after fetal development, they are described as __________.

postmitotic

The conical, triangular transition region of the neuron cell body where the axon originates is the __________.

axon hillock

The structural class of sensory neurons depicted here, which feature a single short process that splits into a peripheral and a central process, is termed __________.

unipolar (pseudounipolar)

The star-shaped glial cells of the central nervous system shown wrapping brain capillaries to help form the blood-brain barrier are __________.

astrocytes

In the peripheral nervous system, myelin sheaths are formed around axons by individual cells called __________ or Schwann cells.

neurolemmocytes

The resting membrane potential of a neuron is typically $-70\,mV$, established predominantly by the continuous diffusion of __________ out of the cell via leak channels.

$$\text{K}^+$$

A graded, postsynaptic potential that results in local membrane depolarization is specifically termed an __________.

excitatory postsynaptic potential (EPSP)

When a single presynaptic neuron repeatedly releases neurotransmitter to generate multiple EPSPs in rapid succession at the initial segment, this is known as __________ summation.

temporal

As illustrated in this action potential step, repolarization is driven by the opening of voltage-gated channels that allow the rapid exit of __________.

$$\text{K}^+$$

The rapid mode of action potential propagation in myelinated axons, where impulses appear to jump between neurofibril nodes, is termed __________ conduction.

saltatory

The arrival of an action potential at the transmissive segment triggers the influx of __________ through voltage-gated channels to induce neurotransmitter exocytosis.

$$\text{Ca}^{2+}$$

The four main chemical categories of neurotransmitters are acetylcholine, amino acids, monoamines (biogenic amines), and __________.

neuropeptides

The neuronal circuit organization shown here, where input from a single presynaptic neuron spreads out to activate multiple postsynaptic neurons, is a __________ circuit.

diverging

As defined in skeletal and neuroanatomy, a narrow slit formed within an individual bone or between adjacent bones is termed a __________.

fissure

During embryonic brain development around week $5$, the primary brain vesicle prosencephalon subdivides into the telencephalon and the __________.

diencephalon

The thin, delicate innermost layer of the cranial meninges that directly adheres to the contours of the brain surface is the __________.

pia mater

The narrow channel shown here that connects the third ventricle to the fourth ventricle through the midbrain is the __________.

cerebral aqueduct

The fifth lobe of the cerebrum, which cannot be viewed from the lateral surface without retracting the temporal lobe, is the __________.

insula

Voluntary somatic motor control originates primarily from the precentral gyrus of the frontal lobe, also termed the __________ motor cortex.

primary

The primary sensory cortex located deep within the insula that is responsible for receiving and processing taste sensations is the primary __________ cortex.

gustatory

White matter tracts that interconnect corresponding areas between the left and right cerebral hemispheres, such as the corpus callosum, are classified as __________ tracts.

commissural

The endocrine structure located in the epithalamus that synthesizes and secretes melatonin to help regulate the sleep/wake cycle is the __________ gland.

pineal

Parkinson disease results from the degeneration of dopamine-producing neurons housed within the midbrain region known as the __________.

substantia nigra

On the anterior surface of the medulla oblongata, the prominent longitudinal ridges where direct pyramidal motor tracts cross the midline are called the __________.

pyramids

The internal branching, treelike distribution of white matter within the cerebellum is known as the __________.

arbor vitae

The paired nerve tracts linking the cerebellum to the pons are designated the __________ cerebellar peduncles.

middle

The component of the limbic system that is specifically responsible for forming long-term memories is the __________.

hippocampus

During a typical sleep cycle, non-REM sleep accounts for approximately __________ of total sleep duration.

$$75\%$$

The cortical region located in the left hemisphere that is dedicated to the comprehension and interpretation of written and spoken language is __________ area.

Wernicke

Olfactory nerve (CN I) fibers leave the nasal cavity and pass superiorly into the anterior cranial fossa via the __________ of the ethmoid bone.

cribriform plate

The motor cranial nerve highlighted in this illustration, which innervates the lateral rectus muscle to abduct the eyeball, is the __________ nerve.

abducens (CN VI)

The cranial nerve shown traversing the neck, thorax, and abdomen to deliver parasympathetic innervation to the heart, lungs, and gut is the __________ nerve.

vagus (CN X)

The human spinal cord tapers to a cone-shaped terminus called the conus medullaris, which typically ends at the vertebral level of __________.

$$L_1$$

The human body possesses a total of __________ pairs of spinal nerves.

$$31$$

Cell bodies of pseudo-unipolar sensory neurons entering the spinal cord are situated within the __________ ganglion.

posterior root (dorsal root)

To safely sample cerebrospinal fluid while avoiding the spinal cord, a lumbar puncture needle is clinically inserted below $L_1$, typically at or below the level of the __________ vertebra.

$$L_4$$

In the spinal cord cross section shown, somatic motor neuron cell bodies that innervate skeletal muscles are located in the __________ horns of gray matter.

anterior

Lateral horns containing preganglionic autonomic motor cell bodies are found only within spinal cord segments $T_1$ through __________.

$$L_2$$

In an ascending somatosensory pathway, the interneuron that relays signals from the spinal cord to the thalamus or brainstem is designated the __________ neuron.

secondary

Direct descending motor pathways controlling skeletal muscle activity are alternately designated as __________ pathways because their fibers form the medullary pyramids.

pyramidal

A specific strip or segment of skin supplied by cutaneous sensory axons of a single spinal nerve is referred to as a __________.

dermatome

The phrenic nerve, which supplies motor innervation to the diaphragm, arises from anterior rami of spinal segments $C_3$, $C_4$, and __________.

$$C_5$$

The terminal nerve of the posterior cord of the brachial plexus that innervates the deltoid and teres minor muscles is the __________ nerve.

axillary

The largest and longest nerve in the human body, arising from the sacral plexus before splitting into the tibial and common fibular nerves, is the __________ nerve.

sciatic

A reflex characterized by direct synaptic communication between a sensory neuron and a motor neuron without an intervening interneuron is termed a __________ reflex.

monosynaptic

During withdrawal from a noxious stimulus on one side of the body, contralateral interneurons cross the midline to activate opposite extensors in the __________ reflex.

crossed-extensor

Unlike the somatic motor system which innervates skeletal muscle, the autonomic motor division innervates smooth muscle, cardiac muscle, and __________.

glands

The parasympathetic division of the autonomic nervous system is anatomically known as the __________ division.

craniosacral

The preganglionic neurons of the sympathetic nervous system have their cell bodies located in the lateral gray horns of spinal segments $T_1$ through __________.

$$L_2$$

Parasympathetic ganglia located either immediately adjacent to or embedded directly within the effector organ wall are termed terminal or __________ ganglia.

intramural

The bilaterally paired chains of paravertebral ganglia that lie immediately lateral to the vertebral bodies are the __________ trunks.

sympathetic

Parasympathetic preganglionic fibers destined to contract the pupillary constrictor muscle run within the __________ nerve (CN III).

oculomotor

The nerve plexus of the enteric nervous system situated between the circular and longitudinal smooth muscle layers of the muscularis externa is the __________ plexus.

myenteric

In both divisions of the autonomic nervous system, all preganglionic axons release the neurotransmitter __________.

acetylcholine (ACh)

Most postganglionic sympathetic axons release norepinephrine at their target effectors and are therefore classified as __________ fibers.

adrenergic

Dual autonomic innervation exhibits cooperative action in the male sexual response, where erection is driven by the parasympathetic division and ejaculation is driven by the __________ division.

sympathetic

Sensory receptors that detect internal stimuli from viscera and blood vessels to monitor the internal environment are classified as __________.

interoceptors

The bare, unencapsulated dendritic endings illustrated here that reside close to the skin surface to detect pain and temperature are __________ nerve endings.

free

The large encapsulated tactile receptor shown here, characterized by concentric layers of neurolemmocytes and connective tissue for detecting deep pressure and high-frequency vibration, is a __________ corpuscle.

lamellated (Pacinian)

According to dermatomal pain mapping, cardiac pain is referred to the pectoral region and left medial arm because sympathetic afferents from the heart share spinal cord segments $T_1$ through __________.

$$T_5$$

Unlike other special sensory systems, the olfactory pathway is unique because sensory tracts travel directly to the cerebral cortex without an obligatory relay in the __________.

thalamus

The largest and least numerous lingual papillae shown, which form a V-shape on the posterior tongue surface and house hundreds of taste buds, are the __________ papillae.

vallate (circumvallate)

The intermediate, highly vascular tunic of the eye wall shown containing the choroid, ciliary body, and iris is the __________ tunic.

vascular (uvea)

During the accommodation reflex for near vision (under $20\text{ feet}$), contraction of the ciliary muscle relaxes the zonule fibers, causing the lens to become more __________.

spherical (convex)

In complete darkness, photoreceptor cells remain depolarized and continuously release the inhibitory neurotransmitter __________ to prevent bipolar cell firing.

glutamate

In the visual pathway, ganglion cell axons originating from the __________ region of each retina cross to the opposite side of the brain at the optic chiasm.

medial (nasal)

In the auditory pathway, high-frequency sound waves cause maximum displacement of the basilar membrane near the __________ of the cochlea.

oval window (base)