Exam One Flashcards
pia mater
the innermost of the three layers of the meninges which is closely applied to the surface of the brain
hypothalamus
a collectional of small but critical nuclei in the diencephalon that lies just inferior to the thalamus; governs reproductive, homeostatic, and circadian functions
oligodendrocyte
provides CNS myelination
third ventricle
a narrow midline space between the right and left diencephalon
temporal lobe
the hemispheric lobe that lies inferior to the lateral fissure
cranial nerve IX
glossopharyngeal - taste, baroreceptors and chemoreceptors
mesencephalon
the midbrain
the most rostral portion of the brainstem; identified by the superior and inferior colliculi on its dorsal surface, and the cerebral penduncles on its ventral aspect
cranial nerve XI
accessory - shoulder and neck muscles
NG2 cell
an oligodendrocyte progenitor cell that can form astrocytes, and possibly neurons
afferent
a neuron or axon that conductions action potentials from the periphery TO the CNS
(A before E, afferent before efferent, must recieve info from periphery to be able to send a response to the periphery)
ventral roots
the collection of nerve fibers containing motor axons that exit ventrally from the spinal cord and contribute the motor component of each segmented spinal nerve
threshold potential
the level of membrane potential at which an action potential is generated
neuropile
the dense tangle of axonal and dendritic branches, and the synapses between them, that lies between neuronal cell bodies in the gray matter of the brain and spinal cord
parietal lobe
the lobe of the brain that lies between the frontal lobe anteriorly, and the occipital lobe posteriorly
horizontal (transverse) sections
any section that runs parallel to the floor, divides brain into superior and inferior sections
sympathetic chain ganglia
located just ventral and lateral to the spinal cord. The chain extends from the upper neck down to the coccyx
What produces membrane potential?
- the Na+/K+ ATPase
- unequal distribution of ions accross the cell membrane
- the Nernst potential (electrochemical gradient)
- ion channels provide current flow through the membrane
cranial nerve I
olfactory - sense of smell
outward current
K+ by delayed rectifer IK(V)
reversal potential
membrane potential of a postsynaptic neuron (or other target cell) at which the action of a given neurotransmitter causes no net current flow
inward current
Na+, Ca2+ movement using voltage-sensative Na+ channel INa(V)
ganglion
cluster of neurons with a central neuropile
axon
the neuronal process that carries the action potential from the nerve cell body TO a target point
(A=Away from cell body)
sensory neuron
conducts impulses from the periphery of an organ to the CNS
telencephalon
the part of the brain derived from the anterior part of the embryonic forebrain vesicle; includes the cerebral hemispheres (cerebrum)
pons
one of the three components of the brainstem, lying between the midbrain rostrally and the medulla caudally
fourth ventricle
a larger space in the dorsal pons and medulla
Nernst equation
a mathematical formula that predicts the electrical potential generated ionically across a membrane at electrochemical equilibrium
meninges
the external covering of the brain; includes the dura mater, arachnoid mater, and pia mater
cingulate gyrus
prominant gyrus on the medial aspect of the hemisphere, lying just superior to the corpus callosum; forms part of the lymbic system
cerebellum
prominant hindbrain structure concerned with motor coordination, posture, and balance. Composed of a three layered cortex and deep nuclei; attached to brainstem by the cerebellar neduncles
occipital lobe
the posterior lobe of the cerebral hemisphere; primarily devoted to vision
astrocyte
controls the environment of neurons, provides signaling
interneuron
technically; a neuron in the pathway between primary sensory and primary effector neurons; more generally, a neuron whose relatively short axons branch locally to innervate other neurons
dendrite
a neural process arising from the nerve cell body that RECIEVES synaptic input
cranial nerve VIII
vestibulocochlear - hearing and balance
cerebrum
largest part of the brain
basal ganglia
a group of nuclei lying deep in the subcortical white matter of the frontal lobes that organize motor behavior. The caudate, putamen, and globus pallidus are the major components of the basal ganglia; the subthalamic nucleus and substantia nigra are often included
medulla
the caudal portion of the brainstem, extending from the pons to the spinal cord
membrane potential
the voltage which exists across the membrane of a cell
voltage-gated ion channels
ion channels whose opening and closing is sensitive to membrane potential
myelencephalon
the most posterior region of the embryonic hindbrain, from which the medulla oblongata develops
cranial nerve XII
hypoglossal - movements of the tongue
myelin
the multilaminated wrapping around many axons formed by oligodendrocytes or Schwann cells
frontal lobe
one of the four lobes of the brain; includes all of the cortex that lies anterior to the central sulcus and superior to the lateral fissure
sympathetic nervous system
a division of the ANS in vertebrates comprising, for the most part, adrenergic ganglion cells located relatively far from the related end organs
diencephalon
portion of the brain that lies just rostral to the midbrain; comprises the thalamus and hypothalamus. Together with the telencephalon, it composes the prosencephalon
cranial nerve II
optic - vision
axon bouton
terminal bulb at the end of an axon
septum pellucidum
a membranous tissue sheet that forms part of the midline saggital surface of the cerebral hemispheres
Schwann cell
provides PNS myelination
glial cells
- support, protect, and communicate with neurons
- provide myelin around axons to increase speed and efficiency of action potential propagation
amygdala
a nuclear complex in the temporal lobe that forms part of the limbic system; its major functions concern autonomic, emotional, and sexual behavior
parasympathetic nervous system
a division of the ANS in which the effectors are cholinergic ganglion cells located near target organs
cranial nerve X
vagus - ANS functions of gut, sensations of larynx and pharynx, vocal cords, swallowing
satellite cell
surrounds neurons in ganglia
dura mater
the thick external covering of the brain and spinal cord; one of the three components of the meninges
hippocampus
a cortical structure in the medial portion of the temporal lobe; in humans, concerned with short-term declarative memory among many other functions
pineal gland
midline neural structure lying on the dorsal surface of the midbrain; important in the control of circadian rhythms
cranial nerve V
trigeminal nerve - sensory information of the face; chewing, biting
thalamus
a collection of nuclei that forms the major component of the diencephalon. Although its functions are many, a primary role of the thalamus is to relay sensory information from lower centers to the cerebral cortex
dorsal roots
the bundle of axons that runs from the dorsal root ganglia to the dorsal horn of the spinal cord, carrying sensory information from the periphery
coronal section
any plane that runs parallel to the face, divides brain into anterior and posterior sections
efferent
a neuron or axon that conducts information AWAY from the CNS towards the periphery
(A before E, afferent before efferent, must recieve info from periphery to be able to send a response to the periphery)
action potential
a momentary all-or-none depolarization of the cell membrane generated when the membrane potential rises above the threshold either spontaneously or because of depolarizing input
rostral
anterior; towards the frontal lobe
dorsal root ganglia (DRG)
the segmental sensory ganglia of the spinal cord; they contain the first-order neurons of the dorsal column/medial lemniscus and spinothalmic pathways
Golgi staining
uses silver salts to stain neurons and their processes
pituitary gland
endocrine structure comprising an anterior lobe made up of any different types of hormone-secreting cells, and a posterior lobe that secretes neuropeptides produced by neurons in the hypothalamus
What are the functions of the nervous system?
- Receive, process, generate, and distribute information
- Control and organize body functions
- Help in communicating with others
- Respond adaptively to the environment with appropriate behaviors that promote survival and reproduction (fitness)
spinal cord
the portion of the CNS that extends from the lower end of the brainstem (the medulla) to the cauda equina
microglial cell
acts as immune cell in CNS
metencephalon
the embryonic part of the hindbrain that differentiates into the pons and the cerebellum.It contains a portion of the fourth ventricle and the trigeminal nerve (CN V), abducens nerve (CN VI), facial nerve (CN VII), and a portion of the vestibulocochlear nerve (CN VIII)
refractory period
the brief period after the generation of an action potential during which a second action potential is difficult or impossible to elicit
enteric system
a subset of the visceral motor system (ANS), made up of small ganglia and individual neurons scattered throughout the wall of the gut, influences gastric motility and secretion
central canal
also known as ependymal canal, it is the cerebrospinal fluid-filled space that runs longitudinally through the length of the entire spinal cord
sagittal section
a vertical plane dividing the brain into left and right sections
cranial nerve IV
trochlear - eye movements
precentral gyrus
the gyrus that lies just anterior to the central sulcus; contains the primary motor cortex
motor neuron
any nerve cell that innervates skeletal muscle
lateral ventricles (first and second)
C shaped; ventral and lateral surfaces are usual defined by basal ganglia, their dorsal surface by the corpus callosum, their medial surface by the septum pellucidum
central sulcus
a major sulcus on the lateral aspect of the cerebral hemispheres that forms the boundary between the frontal and parietal lobes. The anterior bank of the sulcus contains the primary motor cortex; the posterior bank contains the primary sensory cortex
olfactory bulbs
olfactory relay station that recieves axons from cranial nerve I and transmits this information via the olfactory tract to higher centers
cranial nerve VI
abducens - lateral movement of the eye
cranial nerve III
oculomotor - movement of the eye and eyelid
limbic system
refers to those cortical and subcortical structures concerned with emotions; most prominant components are the cingulate gyrus, the hippocampus, and the amygdala
cranial nerve VII
facial - motor control of the face, facial expressions, taste, lacrimal and salivary glands
caudal
posterior; towards cerebellum
neuron
- excitable, generate action potentials
- contain dendrites (input) , soma, and axon (output)
- variable size and shape
arachnoid mater
one of the three coverings of the brain that make up the meninges; lies between the dura mater and pia mater
Action potentials depend on what factors?
- a transient inward current of ions (like Na+ and Ca2+) using a voltage-sensative Na+ channel INa(v)
- followed by an outward current (K+) delayed rectifier IK(V)
lateral sulcus/fissure
the cleft on the lateral surface of the brain that separates the temporal and frontal lobes