nervous system
middle meningeal layer; like a cobweb in structure
arachnoid
structures that return cerebrospinal fluid to the venous blood in the dural sinuses
arachnoid villi
neuron, serving as part of the conduction pathway between sensory and motor neurons
association neuron (interneuron)
neuron type found in the dorsal horn
association neurons (interneurons)
effectors are smooth muscle and glands
autonomic
regulation of blood pressure
autonomic
salivary reflex
autonomic
type of reflex involved in pupillary light reflex
autonomic
subdivision of the PNS that regulates the activities of the heart and smooth muscle, and of glands; it is also called the involuntary nervous system
autonomic nervous system
generally conducts impulses away from the cell body
axon
releases neurotransmitters (neuron anatomy)
axon terminal
feeling a pinch triggers these 2 receptors: ____ and ____
bare nerve endings (pain); lamellated corpuscle
walking on hot pavement triggers these 2 receptors: ____ and _____
bare nerve endings (pain); muscle spindle
the lentiform nucleus, the caudate, and other nuclei are collectively called the ____
basal nuclei
the sympathetic nervous system becomes less efficient as aging occurs, resulting in an inability to prevent sudden changes in ____ when abrupt changes in position are made
blood pressure
fiber type in a spinal nerve
both afferent / efferent
fiber type in the anterior ramus
both afferent / efferent
the other major subdivisions of the brain are the ___ and the ____.
brain stem; cerebellum
the tail-like collection of spinal nerves at the inferior end of the spinal cord is called the ____
cauda equina
some of the fluid continues down the ___ of the spinal cord, but most of it circulates into the ___ by passing through 3 tiny openings in the walls of the ____
central canal; subarachnoid space; fourth ventricle
nervous system subdivision that is composed of the brain and spinal chord
central nervous system (CNS)
normal maturation of the nervous system occurs in a ____ direction, and fine control occurs much later than ___ muscle control
cephalocaudal; gross
responsible for the regulation of posture and coordination of skeletal muscle movements
cerebellum
connects the 3rd and 4th ventricle
cerebral aqueduct
ordinarily, CSF flows from the lateral ventricles to the third ventricle and then through the ____ to the fourth ventricle
cerebral aqueducts
after head injury, retention of water by brain
cerebral edema
the largest part of the human brain is the (paired) ____
cerebral hemispheres
midbrain area that is largely fiber tracts; bulges anteriorly
cerebral peduncle
ventricles in the brain contain ___
cerebrospinal fluid
results when a brain region is deprived of blood or exposed to prolonged ischemia
cerebrovascular accident (CVA)
neck and shoulders (plexus only)
cervical plexus
forms the cerebrospinal fluid
choroid plexuses
cerebrospinal fluid is formed by capillary knots called ___ which hang into the ___ of the brain
choroid plexuses; ventricles
total nonresponsiveness to stimulation
coma
slight and transient brain injury
concussion
are amitotic
neurons
demonstrate irritability and conductivity, and thus transmit electrical messages from one area of the body to another area
neurons
release neurotransmitters
neurons
chemicals released by neurons that stimulate other neurons, muscles, or glands
neurotransmitters
clustered ribosomes and rough ER (endoplasmic reticulum)
nissl bodies
gaps in a myelin sheath
nodes of Ranvier
feeling a caress triggers this receptor: ____
Meissner's (tactile) corpuscle / touch
gray matter is composed of ____
NONmyelinated fibers
a major subdivision of the nervous system that serves as communication lines, linking all parts of the body to the CNS
PNS
transmission of the depolarization wave along the neuron's membrane
action potential
damage to this fiber would lead to a loss of sensory function
afferent
fiber type in the dorsal root
afferent
neuron type in dorsal root ganglion
afferent
neuron that conducts impulses toward the CNS from the body periphery
afferent neuron
beta waves are recorded when an individual is awake and ____
alert
progressive degeneration of the brain with abnormal protein deposits
alzheimer's disease
white matter includes:
anterior commisure; corpus callosum; pyramids; cerebellar peduncle
site of regulation of water balance and body temperature
hypothalamus
able to divide; therefore are responsible for most brain neoplasms
neuroglia
support, insulate, and protect cells
neuroglia
location of the nucleus
neuron cell body
a major subdivision of the nervous system that interprets incoming information and issues orders
CNS
how many synapses occur in this reflex arc?
3
____ pairs of spinal nerves arise from the cord
31
of these pairs, ___ are cervical nervs, ____ pairs are thoracic nerves, ___ are lumbar nerves, and ___ are sacral nerves
8;12;5;5
the specialized motor speech area is located at the base of the precentral gyrus in an area called ____ area
Broca's
specialized cells that myelinate the fibers of neurons found in the PNS
Schwann cells
tramautic injury that destroys brain tissue
contusion
large fiber tract connecting the cerebral hemispheres
corpus callosum
gray matter includes:
cortex of cerebellum; basal nuclei; thalamic nuclei
sensory receptors found in the skin, which are specialized to detect temperature, pressure changes, and pain
cutaneous sense organs
the usual cause of decreasing efficiency of the nervous system as a whole is ____.
decreased oxygen to the brain
conducts local electrical currents toward the cell body
dendrite
state in which the resting potential is reversed as sodium ions rush into the neuron
depolarization
its outer layer forms the periosteum of the skull
dura mater
outermost covering of the brain, composed of tough fibrous connective tissue
dura mater
damage to this fiber type results in a loss of motor function
efferent
fiber type in the ventral root
efferent
neuron type found in the ventral horn
efferent (motor neuron)
neuron that conducts impulses away from the CNS to muscles and glands
efferent neuron
the largest parts of the motor homunculi are the lips, tongue, and ____
fingers
a ___ EEG is evidence of clinical death
flat
the spinal cord extends from the ___ of the skull to the ____ region of the vertebral column.
foramen magnum; lumbar
short term memory is in the ___ lobe
frontal
the primary motor area in the ____ lobe is involved in the initiation of voluntary movements
frontal
collection of nerve cell bodies found outside the CNS
ganglion
muscle sensations when rowing a boat trigger these 2 receptros: ____ and _____
golgi tendon organ; muscle spindle
a ___ is an elevated ridge of cerebral cortex tissue
gyrus
if its drainage is blocked, a condition called ___ occurs, which results in increased pressure on the brain
hydrocephalus
body temperature regulation is a problem in premature infants because the ___ is not yet fully functional
hypothalamus
part of the limbic system; contains centers for many drives (rage, pleasure, hunger, sex)
hypothalamus
three major functions of the nervous system are ____, ____, and ____
interpret information; monitor information; commands responses
may cause medulla oblangata to be wedged into foramen magnum by pressure of blood
intracranial hemorrhage
leaning on a shovel triggers this receptor: ___
lamellated corpuscle
in most humans, the area that controls the comprehension of language is located in the ____ cerebral hemisphere
left
the right cerebral hemisphere receives sensory input from the ___ side of the body
left
abdominal wall (plexus only)
lumbar plexus
anterior thigh
lumbar plexus
the meninges, which cover the spinal cord, extend more inferiorly to form a sac from which the CSF can be withdrawn without damage to the spinal cord, a process called ____
lumbar tap / puncture
contains autonomic centers, which regulate blood pressure and respiratory rhythm, as well as coughing and sneezing centers
medulla oblangata
composed of dura mater, pia mater, and arachnoid villi
meninges
protect the brain
meninges
nerves carrying both sensory and motor fibers are called ____ nerves, whereas those carrying just sensory fibers are referred to as sensory, or ___ nerves
mixed; afferent
autoimmune disorder with extensive demyelination
multiple sclerosis
increases the speed of impulse transmission
myelin sheath
white matter is composed of ____, which provide for communication between different parts of the brain as well as with lower CNS centers
myelinated fibers
another name for a bundle of nerve fibers is ____
nerve (fascicle)
the primary visual cortex is in the ____ lobe of each cerebral hemisphere
occipital
cerebral palsy involves crippling neuromuscular problems and usually is a result of a lack of ___ to the infant's brain during delivery.
oxygen
arises from cranial and sacral nerves
parasympathetic
constricts eye pupils, decreases heart rate
parasympathetic
has more specific control
parasympathetic
long preganglionic axon; short postganglionic axon
parasympathetic
normally in control
parasympathetic
postganglionic axons secrete acetylcholine; cholinergic fibers
parasympathetic
nervous system subdivision that is composed of the cranial and spinal nerves and ganglia
peripheral nervous system (PNS)
leg and foot (2)
peroneal / tibial nerves
diaphragm
phrenic nerve
innermost covering of the brain; delicate and vascular
pia mater
the ventral rami of spinal nerves C1 through T1 and L1 through S4 take part in forming ___, which serve the ___ of the body
plexuses; limbs and anterolateral body trunk
electrical condition of the plasma membrane of a resting neuron
polarized
contains reflex centers involved in regulating respiratory rhythm in conjunction with lower brainstem centers
pons
the primary somatosensory area of the cerebral hemisphere(s) is found in the _____ gyrus
postcentral
the posterior rami of the spinal nerves serve the ____
posterior body trunk
the chief positive intracellular ion in a resting neuron
potassium ions
the primary motor cortex is located in the ____ gyrus
precentral
sensory receptors found in muscle and tendons that detect their degree of stretch
proprioceptors
the ____ tract is the major descending voluntary motor tract
pyramidal
period of repolarization of the neuron during which it cannot respond to a second stimulus
refractory period
period during which potassium ions diffuse out of the neuron
repolarization
state in which all voltage gated Na ions and K ion channels are closed
resting period
as a rule, CSF is formed and drained back into the venous blood at the ___ rate
same
posterior thigh
sciatic nerve
a change in intellect caused by a gradual decrease in oxygen delivery to brain cells is called ___
senility
what tissue is the effector?
skeletal muscle
proccess by which ATP is used to move Na ions out of the cell and K ions back into the cell; completely restores the resting conditions of the neuron
sodium-potassium pump
flexor reflex
somatic
type of reflex involved in effectors are skeletal muscles
somatic
subdivision of the PNS that controls voluntary activities such as the activation of skeletal muscles
somatic nervous system
type of reflex involved in patellar (knee-jerk) reflex
somatic reflex
sensations such as touch and pain are integrated in the _____
somatosensory association
changes, occurring within or outside the body, that affect nervous system functioning
stimuli
list in order the minimum elements in a reflex arc from the stimulus to the activity of the effector
stimulus, receptor, afferent neuron, efferent neuron, effector organ
death of brain neurons, which results from a sudden cessation of oxygen delivery, is called a ____
stroke (CVA)
the convolutions see in the cerebrum are important because they increase the ___
surface area
arises from spinal nerves T1 to L3
sympathetic
causes a dry mouth, dilates bronchioles
sympathetic
fight-or-flight system
sympathetic
postganglioninc axons secrete norepinephrine; adrenergic fibers
sympathetic
short preganglionic axon, long postganglionic axon
sympathetic
junction or point of close contact between neurons
synapse
cortical areas involved in audition are found in the ____ lobe
temporal
encloses the 3rd ventricle
thalamus
important relay station for afferent fibers traveling to the sensory cortex for interpretation
thalamus
what is the stimulus?
the pin prick
the ventral rami of T1 though T12 run between the ribs to serve the ____.
thorax
bundle of nerve processes inside the CNS
tract
a ministroke; fleeting symptoms of a CVA
transient ischemic attack (TIA)
the cavities found in the brain are called ____
ventricles