Nervous System (General) Flashcards
What are ganglion?
Clusters of cell bodies in the peripheral nervous system
What is a nucleus?
a cluster of cell bodies in the central nervous system; is post-mitotic, therefore cannot replicate itself; connected to synapses, not cytoplasm
What are nerves?
A collection of neuron axons in the PNS
What are tracts?
Collections of neuron axons in the CNS
How would you describe sensory nerves that are directed towards the brain?
afferent
What would you consider tracts that move away from the brain?
efferent
What is grey matter?
Nervous tissue that has unmyelinated neuronal cell bodies and axons (such as the neocortex)
What is white matter?
Myelinated axons with neuronal tracts
What are layers or nuclei?
well-defined group of neuronal cell bodies (many, vs. nucleus of neuron)
What is the parenchyma?
the tissues/cells associated with brain function e.g. neurons and glia)
What is, and what does a neuron do?
an individual cell that is ‘electrically irritable’ communicating and computing cells of nervous system
What is, and what is the function of glia?
Supporting cells for immune and structural support (prevents infections, etc.) which aid in the transfer of materials from blood to neurons, etc.
What are the 3 main types of functional cells?
Sensory, motor, and interneurons
What are sensory neurons?
Afferent neurons that carry info. from receptors in the PNS to the brain
What are motor neurons?
efferent neurons that carry signals from the brain (CNS) to the muscles
What are interneurons?
Those which are not connected only to other neurons, not muscles or receptors
What is the morphologic diversity of neurons
the shape of neurons, and their arborization
What is described as a highly-arborized neuron?
Those which are densely-branched, and therefore with many dendrites for a multitude of channels, as opposed to highly-specialized neurons in low-arborization
What would you consider s neuron that has two facets?
bipolar neuron
What is an astrocyte?
a star-shaped glia cell which regulates the transmission of electrical impulses within the brain
What are microglia?
Tiny cells in the brain (roughly encompassing 10 - 15% of brain cells) which are macrophages of foreign bodies, acting as a main defense in CNS
What are macrophages?
cells which takeover foreign cells, etc. by ‘eating’ them; usually a process of immunal support
What are ependymal cells?
Cells which line the cerebrospinal fluid-filled ventricles in the brain, and central canal of the spinal cord; nervous tissue cells with ciliated simple columnar form like mucosal or epithelial cells
What are oligodendrocytes?
Cells which wrap around a select few cells, which cannot regenerate if damaged (in the CNS); provide support and insulation to axons in CNS of some vertebrates
What are Schwann cells?
Cells on the PNS that wrap around cells to provide support and insulation to the axons, and can regenerate of damaged; similar to the oligodendrocytes of the CNS
What are myelin sheath composed of?
80% lipid, 20% protein
What are neural units?
Those individual units in the brain (rather thsn the rest of the body)that contain specialized features: dendrites, axons, cell body
What is the law of dynamic polarization?
the idea that neurons are directed by the dendritic tree, followed by the axons, flowed by synaptic terminals, being depicted from left to right
What are synapses?
Barriers to transmission between two neurons
What is the unity of transmission idea?
The idea that if a neuron passes as excitstoru or inhibitory, it will continue to be so because the probability of neural transmission is either likely or not, respectively
What is Dale’s Law?
The idea that each nerve terminal in a neuron releases a single type of transmitter
What is an axon?
A structure in neural transmission that is between the hillock and a dendrite of another neuron
What is cytoplasm?
jelly-like substance that runs along the axon
What is the non-cytoplasm material that is found near the synaptic cleft?
The interstitium (found in interstitial spaces)
What is neural activity that belongs to the preceding neuron in an exchange?
The presynaptic membrane
What is neural activity that belongs to the proceeding neuron in an exchange?
Postsynaptic membrane
What is the central nervous system composed of?
the brain and the spinal cord
What is the peripheral nervous system composed of?
the sensorimotor or somatic nervous system, as well as the autonomic nervous system
What is the parasympathetic nervous system?
The part of the peripheral nervous system that balances internal/ organs
What is the circular structure that cradles neural transmitters as it moves along the neuron?
the Circle of Willis?
What supports the central nervous system?
the skull and vertebrae
What part of the brain is the neurocranium, and what is it?
found in the posterior portion of the skull, it protects the brain and is inflexible in adults, but not in newborns to ensure the successful travek through the birth canal
What composes the vertebral column?
33 articulated bones that are flexible, and protect the spinal cord
What are the meninges?
3 membranes that enclose the CNS
What is the Dura Mater?
The outer layer of the meninges, a membrane that encloses the CNS in the brain
What is the arachnoid Mater?
The middle layer of the meninges, membranes that enclose the CNS
What is the Pia Mater?
The most closest layer of the meninges to the brain, membranes that enclose the CNS
What is cerebrospinal fluid?
that which cushions the brain and spinal cord from injury, as well as contains immunological support
What are the main bones of the skull?
The parietal, frontal, maxilla, nasal, mandible, zygomatic, temporal, and occipital bones, and the posterior cranial fossa, middle cranial fossa, and anterior cranial fossa
What incorporates the CSF?
the subarachnoid space
What hole do the left and right carotid arteries and left and right vertebral arteries ascend in the neck to supply blood to brain parenchyma?
the foramen magnum
What are the three arteries in the brain?
the anterior, middle, and posterior arteries
What is a stroke?
Bleeding from the arteries and/or veins within the brain
What is thrombosis?
A blood clot in the arteries
What is the internal brain damage that can occur from a serious concussion?
white matter that shears or stretches from injuries, which also may include internal bleeding
What are neurotransmitters?
…
What is the central nervous system?
the part of the vertebrate nervous system located within the skull and spine
What is the peripheral nervous system?
the part of the vertebrate nervous system located outside the skull and spine
What is the cervical region?
the section of the spine that provides the flexible framework of the neck or cervix; it’s between the skull and the thoracic region
thoracic region
the section of the spine to which the ribs are attached; itloes between the cervical region and the lumbar region
lumbar region
the section of the spine that supports the small of the back; it lies between the thoracic and the sacral regions
sacral region
section of the spine to which the bones of the pelvis are attached; lies adjacent to the lumbar region
somatic nervous system
division of the PNS that interacts with the external environ; it conducts sensory signals to the CNS from external receptors and receptors in joints and skeletal muscles, and it conducts motor signals from the CNS to skeletal muscles
autonomic nervous system
division of the PNS that regulates internal rnvironment; conducts signals to the CNS from receptors in internal organs, and motor signals from the CNS back to the same internal organs
spinal grey matter
h-shaped area of gray nervous tissue in the core of the spinal cord (unmyelinated axons)
spinal white matter
area of white nervous tissue in the spinal cord; surrounds the spinal grey matter (myrlinated axons);
dorsal roots
32 pairs of sensory nerves belonging to the spinal cord; they enter the spinal cord’s dorsal (back) surface
central roots
32 pairs of motor nerves that enter the spinal cord; project from the spinal cord’s ventral (front) surface
sympathetic nervous system
1 of 2 motor divisions of the autonomic nervous system; mobilizes energy resources during periods of threat; sympathetic nerves project from thoracic and lumbar regions of spinal cord
autonomic nervous system
1 of 2 motor divisions of the autonomic nervous system; conserves energy during periods of quiescence; parasymparhetic nerves project from brain and from the sacral region of the spinal cord
some effects of sympathetic activity
dilated pupils, increased sweating, decreased salivation, decreased digestion, increased heart rate, erect hair, dilated lungs, stimulated adrenaline release, dilated most blood vessels
some effects of parasympathetic activity
constricts pupils, increases salivation, decreases heart rate, increases digestion, constricts lungs, constricts some blood vessels
of bones in cervical region of spine
8
of bones in thoracic region of spinal cord
12
of bones in lumbar region of spine
4
of bones in sacral region of spinal cord
5
pituitary gland
gland of the endocrine system that hangs from the hypothalamus; because it releases tropic hormones (releases hormones to encourage other glands’ release of hormones), therefore is referred as the master gland
hypothalamus
brain structure from which the pituitary gland is suspended; secretes releasing hormones, which stimulate the release of tropic hormones from the pituitary
adrenal medulla
cord of the adrenal gland, stop the kidneys; activated by the parasymparhetic nervous system, it secretes hormones whose effects are similar to those of the sympathetic nervous system
adrenal cortex
outer layer of the adrenal gland, located above the kidneys; releases hormones that regulate energy metabolism, mineral balance, and reproductive behaviour
gonads
sex glands (ovaries, tested) that release hormones that influence the development of fe/male reproductive systems and the reproductive behavior of adults
What type of electrical signal is created within neurons, near the axon hillock that rapidly attenuates, and is useful for signally over a very short distance in high intensity?
graded potentials
What type of electrical signal is created within neurons, near the axon hillock, resulting in an ‘all-or-none’ signal that propagates along the whole axon to the synapse, useful over long distances?
action potentials
What must be able to:
- ‘bind’ to receptors on the receiving neuron, causing changes in the selective ionic permeability of its post-synaptic membrane
- be synthesized in the transmitting neuron
- be released by the transmitting neuron into the synaptic cleft
- be able to be decomposed in the synaptic cleft by enzymatic action
- be able to bind to receptors on the presynaptic membrane, causing reduced _ release?
the neurotransmitter
What changes are created as a result of synaptic transmission, and the electrical properties of the receiving neuron?
postsynaptic potentials
Where within the neuron are post-synaptic potentials within the receiving neuron that forms the basis of the neuron’s signalling and information processing activities?
the postsynaptic neuron’s dendritic tree
What are EPSPs?
Excitatory post synaptic potentials that are created in the receciving neuron’s dendrites and increase the likelihood of the production of an action potential on its axon
What are IPSPs?
inhibitory post synaptic potentials created in the receiving neuron’s dendrites that decrease the likelihood of the production of an action potential on its axon
Where do most neurons produce both EPSPs and IPSPs which are integrated over both space and time?
the soma
Where is an action potential (most likely) created?
in the axon hillock
What line the CSF-filled ventricles in the brain and the central canal of the spinal cord, as nervous tissue cells with a ciliated simple columnar form much like that of some mucosal epithelial cells?
ependymal cells
What type of cells are undifferentiated with a capacity for self-renewal, and give rise to progenitor cells?
neural stem cells
What cells develop from stem cells and give rise to blasts?
progenitor cells
What cells are primitive types of nervous system cells, and develop into neurons or glia?
blasts
Which bones form the base of the skull?
the anterior, middle, and posterior cranial fossae
What arteries provide blood circulation to the brain (from top to bottom)?
anterior cerebral artery, anterior communicating artery, circle of willis, left and right middle cerebral arteries, posterior cerebral arteryies, posterior communicating arteries, Basilar artery, external carotid arteries, vertebral arteries, internal carotid arteries, and common carotid arteries
Which arteries are a part of the Circle of Willis?
the anterior communicating artery, the posterior cerebral arteries, and the Basilar artery
What is a stroke also known as?
an intraparenchymal or intracerebral hematoma
What occurs when trauma is accompanied by white matter ‘shear’ injuries (stretching or shearing of myelinated axon tracts), which can result in severe brain damage?
an intraparenchymal hematoma
What in white matter can be sheared or stretched during a stroke?
myelinated axon tracts
What are different from the cerebral arteries in mainly supplying blood to the region of the meninges?
the meningeal arteries, anterior, middle, and posterior, which irrigate the anterior, middle, and posterior cranial fossae, respectively
What are these symptoms of?
- slurred speech
- headache
- the inability to speak
- loss of consciousness or coma
- numbness (may be in several areas of the body)
- seizures
- visual problems
- weakness
subdural hematoma
What shape do the lateral ventricles, third ventricle, cerebral aquaduct, fourth ventricle, and central canal make?
the female reproductive system
What develops from the neural plate during embryogenesis?
the brain/encephalon
What is the acronym for the parts of the adult brain (encephalon)?
TDMMM
- Telencephalon
- Diencephalon
- Mesencephalon
- Metencephalon
- Myelencephalon
What part of the brain are cortical areas or lobes found?
The Telencephalon
What is subcortical white matter?
tracts
What is the acronym for the lobes?
FOPTI
- frontal
- occipital
- parietal
- temporal
- insular
What are these three main structures a part of?
1. neocortex
2. basal ganglia
3. limbic system
(last two are “subcortical” forebrain structures)
forebrain
What is the approximate surface area of the neocortex?
2500 sq. cm, 1.5 - 3 mm thick
Which lobes of homo sapiens are much larger than other primates?
frontal
What is the shape of the temporal pole, inferior temporal gyrus, fusiform gyrus (occipitotemoral gyrus), collateral sulcus, occipitotemporal sulcus, and parahippocampal gyrus?
Like a pretzel that rolls its two ends within itself
At what view are the temporal, and occipital lobes, as well as their subsequent poles, gyri, and sulci best shown?
a posterior view (looking up)
