1.16.25 Neuroanatomy Flashcards
What is a neuron?
nerve cell, basic unit of the nervous nervous
What is a glial cell?
a brain cell that provides structural, nutritional, and other types of support.
Neurons
What is the input zone?
Where neurons collect and process information.
cellular extensions, dendrites, recieve information from other neurons.
What is the integration zone?
where the decision to produce a neural signal is made. information is integrated in the cell body.
What is the condunction zone?
where information can be electrically transmitted over great distances, a single axon, or nerve fiber, conducts output information away rom the cell body as an electrical impulse, axon may split into multiple branches (axon collarerals)
What is an axon hillock?
one-shaped area of the cell body that gives
rise to the axon; gathers and integrates information arriving from the synapses on the dendrites and cell body
What is the axonal transport?
bidirectional movement of materials within an axon
What is the output zone?
specialized swellings at the end of the axons called axon terminals, transmit the neuron’s signals across synapses to other cells.
What are the types of neurons?
-motor
-sensory
-interneurons
What are the types of shapes of neurons?
-multipolar
-bipolar
-unipolar
Neurotransmission
What is the presynaptic neuron?
neuron that is transmitting information
What is the postsynaptic neuron?
neuron recieving information
What is the presynaptic membrane?
membrane on the axon terminal of the presynaptic neuron
What is the postsynaptic membrane?
membrane on the dendrite or cell body of the postsynaptic neuron
What is the synaptic cleft?
The gap that separates the membranes.
What are synaptic vesicles?
Small spheres in presynaptic axon terminal that contain neurotransmitters
What are neurotransmitters?
specialized chemical that server as the basis of communication between neurons.
What are receptors?
Specialized proteins that selectively sense and react to molecules of a corresponding neurotransmitter or hormone. (example; cones and rods)
Oligodendrocyte cells
form myelin sheaths in the brain and
spinal cord
Schwann cells
provide myelin to neurons outside the brain and spinal cord
Nodes of Ranvier
gaps between sections of myelin where
the axon is exposed
Astrocyte cells
star-shaped cells that stretch around and
between neurons and blood vessels; secrete chemicals that affect synaptic transmission and the formation of synapses; help form outer membrane around the brain
Microglial cells
tiny, mobile cells that remove debris from
injured or dead cells
What is gross neuroanatomy?
Features of the nervous system visible to the naked eye?
What are the contents of the Central nervous system?
The brain and spinal cord
What are the contents of the peripheral nervous system?
All other parts of the nervous ststem outside the brain and spinal cord.
What are motor neurons?
transmit information from the spinal cord and brain to muscles and glands.
What are sensory nerves?
Conveys informtion from the body to the central nervous system.
what are the subcategories in the Peripheral Nervous System?
Somatic
Autonomic
What is the Somatic nervous system?
nerves that interconnect the brain and the major muscles and sensory systems of the body
What is the Autonomic nervous system?
nerves that connect to the
viscera (internal organs)
What nerves make up the Somatic nervous system?
cranial
spinal
What are cranial nerves?
Arise from the brain and innervate the head, neck, and visceral organs directly, without ever joining the spinal cord
What are spinal nerves?
emerged from the spinal cord
What are the sub-categories for the autonomic nervous system?
sympathetic
parasympathetic
Explain the function of the sympathetic nervous system.
prepares the body for action; fight-or-flight
Explain the function of the parasympathetic nervous system.
prepares the body to relax and recuperate (relax and digest)
What is the cerebral hemisphere?
One of the two halves of the forebrain.
What is the cerebral cortex?
the lumpy surface of the brain; folded thick sheet of tissue
What is the cerebral cortex made up of?
dendrites
cell b odies
axonal projections of neurons
What is Gyri
ridges of tissue, ridged or raised portion of the brain surface
What is the sulcus?
crevice that separates the gyri.
What are lobes?
groups of gyri and sulci.
What are the four major cortical regions?
frontal
parietal
temporal
occipital
What is the sylvian fissure?
lateral sulcus, demacrates the temporal lobe
What is the central sulcus?
Distinct landmark dividing the frontal and parietal lobes
What is the corpus collosum?
main band of axons that conncets two cerebral hemispheres; this connection allows the brain to act as a single entity during complex processing.
What is Postcentral gyrus?
Strip of parietal cortex just behind the central sulcus that receives somatosensory information from the entire body; mediates the sense of touch.
What is the precentral gyrus?
Strip of frontal cortex just in front of the central sulcus that is crucial for motor control.
What is gray matter?
brain tissue; areas of the brain that are domincated by cell bodies and are devoid of myelin, recieves and processes information
What is white matter?
light-colored layer of tissue consiting mostly of myelin-sheated axons that lies underneath rgay matter of the cortex, transmits information
Subdivisions
What is the neural tube?
embryonic structure with subdivisions that correspond to future subdivisions of the brain
What is the forebrain?
frontal division of the neural tube, later develops into the telecephalon, or cerebral hemispheres, and the diencephalon, or the thalamus or hypothalamus.
What is the midbrain?
middle division of the brain
What is the hindbrain?
rear division, later develops into the mentencephalon, or cerebellum and pons, and the myelencephalon, or medulla
What is the brainstem?
what we call the cerebellum, pons, and medulla
Nucleus vs Tract
nucleus: a collection of neurons
Tract: a bundle of axons
Vertebrates are…
bilaterally symmetrical
What is beneath the Cerebral cortex?
basal ganglia
limbic system
amygdala
hippocampus
fornix
cingulate gyrus
olfactory bulb
Function of Basal Ganglia
control of movement
Function of Limbic System
emotion and learning
Function of Amygdala
found in the medial temporal lobe
emotional regulation (anger)
Function of Hippocampus
found in the medial temporal lobe
learning and memory
Function of Fornix
fiber tract that extends from the hippocampus to the body
learning and memory
Function of Cingulate gyrus
Strip of cortex in the frontal and parietal midline
cognitive functions
Function of Olfactory bulb
primary input for sense of smell; anterior projection of the brain that conntects to nasal passages
Function of Thalamus
Paired structures that direct the flow of sensory information to and from the cortex (the diagnosee)
Function of Hypothalamus
hunger, thirst, temperature, regulation, sex
What is the Tectum in the midbrain?
two regions process visual and auditory information
What is the motor centers in the midbrain?
Substantia nigra
Red nucleus
Function of substantia nigra
neurons that release dopamine
Function of red nucleus
communicates with motor neurons in the spinal
cord
Function of Reticular formation
involved with sleep and arousal,
temperature control, and motor control
Function of cerebellum
involved in motor coordination and learning
Function of pons
contains motor control and sensory
nuclei and gives rise to cranial nerves
Function of medulla
contains cranial nerve nuclei and nuclei that
regulate breathing and heart rate
What are the three protective membranes? (meninges)
-dura mater
-pia mater
-arachnoid
dura mater
tough, outermost shee
pia mater
delicate innermost layer
arachnoid
substance between the dura and pia mater that cushions the brain in cerebrospinal fluid (CSF
function of ventricular system
series of chambers filled with CSF
What are the two major functions of CSF
acts as a shock absorber
provides an exchange medium between blood and brain
