Lab oral #5 Flashcards
What are the anatomical types of neurons-based upon the number of process attached to cell body
1) Unipolar (Pseudounipolar)
2) Bipolar
3) Multipolar
Unipolar (Pseudounipolar) is
Based upon the number of processes attached to cell body
Bipolar is
One axon and one dendrite (Special sensory neurons)
Multipolar is
One axon and several dendrites (Motor neurons)
Functional types of neurons-based upon relationship with the CNS
1) Sensory (Afferent)
2) Motor (Efferent)
3) Interneuron (Associate)
Carry impulses into CNS
Sensory (Afferent)
Carry impulses away from the CNS
Motor (Efferent)
Carry impulses within the CNS
Interneuron (Associate)
Name the different neuroglia cells
1) Astrocytes (CNS)
2) Oligodendroctyes (CNS)
3) Microglia (CNS)
4) Ependymal cells (CNS)
5) Neurolemmocyte (PNS)
6) Satellite cells (PNS)
Name the 4 types of neuroglia cells that are located in the CNS
1) Astrocytes
2) Oligodendrocytes
3) Microglia
4) Ependymal cells
Name the two types of neuroglia cells that are located in the PNS
1) Neurolemmocyte
2) Satellite cells
Astrocytes are
Large, branching cells that form the blood-brain barrier
Oligodendrocytes are
Cells with few branches that form myelin
Microglia are
Tiny cells with complex branches and are phagocytes
Ependymal cells are
Ciliated & secrete the cerebrospinal fluid (CSF)
Neurolemmocyte are
Myelin producing
Satellite cells are
Isolate and nourish cell bodies in ganglion
What are the nerve connective tissue coverings (PNS)
- Epineurium
- Perineurium
- Endoneurium
- Fascicles
Connective tissue coverings of CNS
Meninges
What are the different Meninges (connective tissue coverings of the CNS) from external to internal
1) Dura mater-tough outer cover
2) Arachnoid membrane- weblike & enclosing the CSF (cerebrospinal fluid)
3) Pia mater- delicate inner, vascular membrane that adheres to the CNS
The nervous system is divided into two main sections which are the
Central nervous system and peripheral nervous system
What is in the CNS?
The brain and spinal cord
What is in the PNS?
Everything else; all the things outside the brain and spinal cord; the spinal nerves, cranial nerves & the peripheral nerves that go to other parts of the body
The two anatomical divisions of the nervous system are?
Central & peripheral nervous system because it has to do with with where those structures are
The basic unit that conducts impulses and thus carries messages throughout the body
The neuron
A typical neuron is composed of
3 main parts; the cell body, the dendrites, and the axon
The dendrites conduct
Impulses towards the cell body
The cell body contains most of the cellular parts including
The nucleus and all of the anatomy that is needed to keep the cell alive and functioning
The axon carries impulses
Away from the cell body
Within the cell body is
The nucleus and the chromatophilic bodies
The chromatophilic bodies are
Large numbers of free and attached ribosomes that stain darkly on real neurons
The many ribosomes are important in producing
Proteins int he active neuron
Neurons are very active and proteins are an important part of
That activity
Within the axons are
Neurofibrils
Neurofibrils are
Bundles of microtubules that serve to make the axon stronger, it is less likely to break because of the neurofibrils
Wrapped around the axon are
Neuroglial cells called neurolemmocytes (Schwann Cells)
The whole neurolemmocyte cell is called a
Neurolemmocyte and the outer portion is called the neurilemma
The neurilemma contains
The nucleus and most of the cells contents
The basic unit that conducts impulses & thus carries messages throughout the body
The neuron
Another part of the neurolemmocyte is wrapped tightly around the axon & is called the
Myelin sheath
A typical neuron is composed of 3 main parts
1) Cell body
2) Dendrites
3) Axon
The neurofibril node is a small gap between the adjacent
Neurolemmocytes
Neurofibril nodes are very important in
High speed conduction
Most sensory neurons are?
Unipolar
These neurons are rare & found only in few places in the body. For example in the retina during sight, during vision
Bipolar
This neuron has many processes coming off the cell body
Multipolar
Most common types of neurons are the
Multipolar & are usually the motor neurons
These conduct impulses but cannot maintain themselves on their own they need helper cells
Neurons
These cells are found associated with ganglion & seem to surround the cell bodies & provide insulation & maybe some protection
Satellite cells (PNS)
These cells connect blood vessels to neurons; they are the blood-brain barrier; they are the barrier between the blood system & the brain; they connect the blood system to the nervous system of the brain. Important cells, without them there would not be nutrients coming from the blood system into the brain, nor would you have hormone communication to the brain
Astrocytes (CNS)
The cells produce & circulate fluid in the central nervous system. This fluid is called cerebrospinal fluid (CSF)
Ependymal cells (CNS)
Cerebrospinal fluid is in the
CNS & produced by the ependymal cells
These cells move about & remove cellular garbage from the CNS. Sort of like macrophages of the WBCs
Microglial (CNS)
These cells produce the myelin sheath of the CNS
Oligodendrocytes
These cells produce the myeline sheath of the PNS
Neurolemmocytes
A nerve is
A bundle of many axons running parallel to one another, these many axons are covered with connective tissues to hold them together
What are the connective tissues for nerves
Neuriums
The axon of a nerve is covered with?
Endoneurium
The bundles of axons are called?
Fascicles that are surrounded by connective tissue called the perineurium
The whole nerve is covered by connective tissue called
Epineurium
The connective tissues covering the brain & spinal cord are called
Meninges
A serious disease occurs when (meninges) membranes become irritated or infected which is called? If it infects the spinal cord it is called?
Meningitis
spinal cord: Spinal meningitis
A tracing is an
Exercises in which you have to follow the pathway that some anatomical process may take
What is RSIME?
Receptor Sensory neuron Interneuron Motor neuron Effector
A stimulus in a reflex arc travels
Up the arm through sensory neuron to the spinal cord where there is an interneuron which connects it to the motor neuron and then the motor neuron running back down the arm to the muscle which is the effector organ. The brain is not involved in this
Gray matter in the spinal cord is located
On the inside
Gray matter in the spinal cord is shaped like
A butterfly with several lobes called horns
A nerve that branches off the cord is called a
Spinal nerve
A nerve that branches off the posterior is called
Posterior root, its a sensory nerve
Motor nerves exit on what side and called what?
Anterior side and called anterior root
The cell bodies of all neurons making up the posterior root are
Clustered into a knob called the ganglion
What houses all of the cell bodies of the sensory neurons?
The posterior root ganglion
Cervical plexus is found
In the neck
Brachial plexus goes
To the arm
The sacral plexus is in
The lower back region and in the hip region
What is a plexus?
A group of nerves in a particular region
The sciatic nerve is a
Branch of the lumbar & sacral nerves and is considered part of the sacral plexus (in the flexible area of the upper leg) (lower buttocks)
Sitting on hard objects can lead to
Sciatica
The cauda equina literally means
Horses tail. It is many branches of the spinal cord in the lumbar region
The filum terminale is
Connective tissue that helps anchor the tip of the spinal cord
Sympathetic trunk is the
Thin strand between each ganglion
Ventricles of the brain are
Cavities within the brain that are filled with a fluid (CSF)
CSF has a slow circulation throughout the ventricles aided by
Pressure and cilia on the edges of ependymal cells
These cells line the ventricles in the brain
Ependymal cells
CSF tracing
Most of CSF is produced by choroid plexus of various ventricles
1) Starts at lateral ventricles
2) Pressure buildup pushed CSF through interventricular foramen
3) Third ventricle (csf added)
4) Moves down through mesencephalic aqueduct
5) Fourth ventricle (csf produced)
*From here the fluid can take different routes
1) Through apertures into the subnarachoid space around the brain
OR
2) Go down through central canal of spinal cord and at cauda equine it enters the subarachnoid space of spinal cord
7) Joins the subarachnoid space around brain
8) Comes together at top of brain
9) Enters arachnoid villi at top of brain and then goes into deral sinuses
CSF is produced in the
Choroid plexuses and is absorbed int he anachnoid villi where it enters the blood stream.
The flow of CSF does what
Cleanses waste material at the surface of the CNS
If blockage occurs along the CSF pathway what happens
It can have serious consequences. The ventricles can build up pressure & enlarge and push out against the brain tissue & damage the brain
What happens to babies if blockage occurs along CSF pathway?
The pressure can greatly enlarge the ventricles pushing against the skull which is unossified, and making the skull become very large increasing the head size dramatically. This is known as hydrocephalus or water on the brain. Children will end up with large heads & may result in mental retardation because of the pressure on the brain damaging the brain tissue. Surgical shunts can treat this disease by relieving the pressure
Cranial nerves are nerves that exit various regions of the
Brain and go to other parts of the body
How many cranial nerves are there?
12 Cranial nerves and they come in pairs so there are 12 pairs of cranial nerves
What is the mnemonic:
OOOTTAFVGVAH
Oh Oh Oh To Touch And Feel Very Good Valuables AH (Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Accessory, Hypoglossal)
