Central Nervous System, Brain And Cranial Nerves Flashcards
(104 cards)
1
Q
What are the principals of cells in the nerve system
A
The nervous system consists of two types of principals
Neuro glial cells - support the nervous system
Nerve cells/neurons - conduct signals
2
Q
What is the sensory function?
A
Receptors detect a stimulus (changes in the environment)
3
Q
Cell body of a neuron
A
Contains nucleus and cytoplasmic organelles
4
Q
Dendrites of an neurone
A
- Conduct impulses to the cell body
- They are all over the place
- they are connected to other nerves
- The stronger the cell signal, the more likelihood of a nerve signal impulse.
5
Q
Axon of a neuron
A
Conducts impulses away from the body to transmits impulses towards another neuron
6
Q
Synapse
A
junction between nerves where a nerve impulse is transmitted
7
Q
Describe the process of generation and propagation of a nerve impulse
A
A neuron receives a stimulus.
The nerve travels to the axon membrane - axon terminal
The axon terminal releases neurotransmitters that carry nerve impulses to the next cell
8
Q
Outline the cells function of nervous system
A
- Neurons send and receive neurotransmitters
- Maintaining homeostasis
- Interpreting sensory information
- Creating motor responses
9
Q
Identify the 4 neuro glial cells in the CNS
A
Astrocytes - star shaped, can become cancerous regulate blood brain barrier, connect capillaries and neurones together, provide nutrients and support for neurones
Microglial cells - convert into macrophages (white blood cells) and engulf pathogens, first line of defence, acts as a way of changing chemical environment
Oligodendrocytes - forms myelinated sheath ( a fatty sheath of myelinated fibres) to transmit signals faster, conserves energy
Ependymal cells - can become cancerous, made up of squamous and columnar cells, sometimes ciliated cells forms csf, filters blood, provides nutrients and support to csf, the ciliated cells help with the circulation of csf in the brain
10
Q
Identify the two neuro glial cells in the PNS
A
Schwann cells - like oligodendrocyte cells, form myelinated sheath to speed up transmission of signals, conserves energy, in pns
Satellite cells - muscle stem cells, located in the periphery of muscle fibre,
11
Q
Describe structure and function of the spinal cord and relationship with the vertabrae
A
The vertebra encloses and protects the spinal cord within the spinal canal.
12
Q
Describe integration of the brain and spinal cord
A
The brain is what controls all the body’s functions.
The spinal cord runs from the brain down through the back.
It contains threadlike nerves that branch out to all organs and body parts
These nerves relays messages back and forth from the brain to different parts of the body.
13
Q
Describe the processes involved with a spinal reflex
A
Receptors - stimulus - something triggers a sensory receptor
sensory neuron - carries the signal from the receptor to the spinal cord
spinal cord - interneurons process the signal
motor neuron - processed signal sent to motor neuron
muscles - motor neuron causes muscles to contract
The path taken by nerve impulse in a reflex action is called a reflex arc.
14
Q
Describe the structure and functional aspects of the autonomic nervous system
A
It regulates functions such as cardiac regulation, vasomotor activity, respiration, reflex activities such as sneezing, swallowing, coughing and vomiting. It works in conjunction with the peripheral nervous system.
The sympathetic nervous system is associated with fight-or-flight response. On the other hand, the parasympathetic nervous system is associated with rest and digest.
15
Q
What is CSF
A
Cerebrospinal fluid (CSF) is a watery liquid that continually circulates through the brain’s ventricles (hollow cavities) and around the surface of the brain and spinal cord.
CSF washes out impurities from the brain, transfers nutrients and provides protective cushioning to the brain and spinal cord.
16
Q
Describe saltatory conduction
A
On myelinated nerves, the signal speeds up bc instead of travelling through each nerve, it can jump between synapses and gaps between nodes of ranvier/Schwann cells
17
Q
*Name the two sets of bones that make up the skull.**
A
Cranial - 8
Facial - 14
18
Q
How are cranial bones different from facial bones?
A
The cranium (skull) is the skeletal structure of the head that supports the face and protects the brain. It is subdivided into the facial bones and the brain case.
The facial bones underlie the facial structures, form the nasal cavity, enclose the eyeballs, and support the teeth of the upper and lower jaws.
19
Q
Which suture articulates the parietal bone with the frontal bone?
A
Coronal suture
20
Q
Name the paired bones that form a large part of the roof of the cranium.**
A
Left and right parietal bones
21
Q
How many bones form the cranium
A
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22
Q
How many parts is the temporal bone divided into?**
A
The temporal bone consists of four parts— the squamous, petrous, mastoid and tympanic parts.
23
Q
What are the features of the squamous portion of the temporal bone?*
A
Largest and most superior positioned
24
Q
Name the parts of the petromastoid division of the temporal bone.**
A
Petrous part. The petrous part is a wedge shaped mass of bone located between the sphenoid and occipital bones within the cranial cavity. It is the most medial part of the temporal bone
25
What features are found on the external surface of the frontal bone?**
Suprciliary arch, - curved arch
Glabella - prominence
26
Where does the frontal bone articulate with the parietal bones
Coronal suture
27
How is the occipital bone internally divided?
28
Name the external features of the occipital bone.**
29
What are the main features of the ethmoid bone?**
The ethmoid bone is a small bone with a cuboidal structure that forms the lateral boundaries of the orbit, the anterior cranial fossa superiorly, and the nasal cavities inferiorly.
It is relatively light and has a spongy texture
30
What does the crista galli project superiorly from?*
Falx cerebri
31
What does the crista galli project superiorly from?**
Falx cerebri
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16. **What shape is the sphenoid bone?**
Butterfly/bat
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17. **Name the parts of the sphenoid bone.**
Optic canal
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18. **What is the key function of the sphenoid bone in the cranium?**
Sphenoid bone has many essential functions. It helps form the base and lateral sides of the skull in combination with the orbital floor.
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19. **What are the functions of facial bones?**
the facial bones serve as protection for the brain and the organs responsible for smell, sight, and taste.
My - mandible - 1
Mouths - maxillary - 2
Palette - parietal bones - 2
Never - nasal bones - 2
Liked - lacrimal - 2
Zucchini - zygomatic - 2
In - inferior nasal conchea - 2
Vinegar - vomer - 1
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20. **Name the bones that form the bridge of the nose.**
Nasal bones
- bridge
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21. **What bones contribute to the formation of the orbit?**
Maxilla
Zygomatic
Lacrimal
Palatine
Frontal
Ethmoid
Sphenoid
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22. **Name the passages in the orbit for the optic nerve.**
enters the bony skull through the optic foramen
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23. **What type of joint is the TMJ?**
synovial joint
consists of articulations between three surfaces; the mandibular fossa and articular tubercle (from the squamous part of the temporal bone), and the head of mandible.
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24. **Name the ligaments associated with the TMJ.*
Lateral ligament
Sphenoidmandibular ligament
Stylomandibular ligament
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25. **List the movements possible at the TMJ.**
Protrusion and retraction
- upper part of the joint allows this
- the lateral pterygoid muscle is responsible
Elevator and depression
- lower part of the joint allows this
Depression is caused by gravity
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31. **Differentiate between the somatic and autonomic nervous systems.**
SNS = voluntary control over skeletal muscles
ANS= involuntary automatic processes
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36. **What is the main difference between grey and white matter?**
differ in colour, compositions d function.
Grey: composed of neutron cell bodies, send tyres and unmyelinated axons, filial cells and
blood verses
White matter- the byline sheaths covering axons . Has myelinated axons which are long
nerve fibres connecting different parts of brain and spinal cord
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37. **Where are nuclei and ganglia located?**
Nuclei - CNS
Ganglia PNS
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38. **Provide examples and functions of multipolar, bipolar, and unipolar neurons.**
Multipolar Neurons:
Structure: Many branches (dendrites) and a long tail (axon).
•Example: Motor neurons in the brain and spinal cord.
Function: Control muscles and process information.
Bipolar Neurons:
Structure: Two branches-~-one from each side of the cell body.
Example: Found in the eyes and nose (retina and olfactory epithelium).
Function: Relay sensory information from specialized organs.
Unipolar (Pseudounipolar) Neurons:
Structure: One short branch splits into two--a central process and a perip process.
Example: Sensory neurons in the spinal cord.
Function: Transmit sensory information from the body to the spinal cord
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39. **Describe the phases of an action potential.**
Resting stage- voltage gated channels closed
Deplarisation phase
Repolarisationpahse
- decrease in sodium ion
- Increase in postasoun ion
Hyperpolsrisation
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40. **What happens during depolarization and repolarization?**
Action potential generated , sodium channels open, potassium’s channels close, positive
inside, negative outside, rise in membrane potential.
Sodium channel close , potassium Chanel open, negative inside, positive outside, drop
membrane potential
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41. **Explain the steps involved in the propagation of an action potential.**
Sodium ion depolarisation of adjacent membrane, opening of sodium ion channels,
repolarisation of membrane at original site of where action potential generate, Resting
potential of membrane restored, Action potential self propagating
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42. **What is the role of sodium ions in this process
Triggers the proper hat ion of the action potential along the Bering allowing the
transmission of signals in the nervous system
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44. **How does the saltatory conduction contribute to the efficiency of nerve impulse conduction?**
improves the efficient of nerve impulse conduction: speed of transmission, energy
conservation, greater bandwidth, signal strength
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45. **List the components of a chemical synapse.**
Presynaptic terminal
Synaptic cleft
Postsynaptic membrane
Neurotransmitter
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46. **Explain the process of neurotransmission at a chemical synapse.**
Action Potential Arrival:
• An action potential, or electrical signal, travels down the axon of the presynaptic
neuron toward the axon terminal.
2. Opening of Voltage-Gated Calcium Channels:
• When the action potential reaches the axon terminal, it triggers the opening of
voltage-gated calcium channels in the presynaptic membrane.
3. Influx of Calcium Ions:
• Calcium ions (Ca2+) rush into the presynaptic terminal due to the open calcium
channels. This influx of calcium serves as a key trigger for the release of
neurotransmitters.
4. Release of Neurotransmitters:
• The increase in calcium concentration inside the presynaptic terminal causes
synaptic vesicles, which contain neurotransmitters, to fuse with the presynaptic
membrane. This fusion releases neurotransmitters into the synaptic cleft.
5. Diffusion Across the Synaptic Cleft:
• Neurotransmitters, now in the synaptic cleft, diffuse across this small gap. The
synaptic cleft is the space between the presynaptic and postsynaptic membranes.
6. Binding to Receptors on Postsynaptic Membrane:
• Neurotransmitters bind to specific receptor proteins on the postsynaptic
membrane of the receiving neuron or effector cell. This binding is highly specific,
like a kev fitting into a locklike a key fitting into a lock.
7. Postsynaptic Response:
The binding of neurotransmitters to receptors induces a change in the
postsynaptic membrane potential. This change may lead to depolarization
(excitatory response) or hyperpolarization (inhibitory response) of the post synaptic cell
8. Termination of Signal:
• The neurotransmitter signal needs to be terminated to avoid continuous
stimulation. This can occur through reuptake of neurotransmitters back into the
presynaptic terminal, enzymatic degradation of neurotransmitters in the synaptic
cleft, or diffusion away from the synapse.
9. Reuptake or Degradation:
• Neurotransmitters can be actively transported back into the presynaptic terminal
by reuptake proteins or broken down by enzymes present in the synaptic cleft.
10. Replenishment of Synaptic Vesicles:
• The presynaptic neuron replenishes synaptic vesicles with neurotransmitters,
preparing for the next action potential and subsequent release of
neurotransmitters.
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47. **How are neurotransmitter effects terminated in a synapse?**
Reuptake:
• Think of it like recycling. After sending the message, the neuron takes back the
neurotransmitters for later use.
2. Enzymatic Breakdown:
• Enzymes act like little cleaners, breaking down neurotransmitters into smaller
pieces that don't have the same signaling effect.
3. Diffusion:
• Sometimes, neurotransmitters just wander away from the synapse, like a scent
fading away in the air.
4. Glial Cell Cleanup:
• Imagine neighboring glial cells as helpful neighbors picking up any leftover
neurotransmitters, keeping things tidy.
48. **How many layers compose the m
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48. **How many layers compose the meninges, and can you name them?**
1. Dura Mater:
• Description: The outermost and toughest layer of the meninges.
Function: Provides a protective covering for the brain and spinal cord.
2. Arachnoid Mater:
• Description: A delicate, web-like membrane located beneath the dura mater.
• Function: Acts as a protective barrier and contains cerebrospinal fluid (SF) in the
subarachnoid space.
3. Pia Mater:
Description: The innermost layer that closely adheres to the surface of the brain
and spinal cord.
• Function: Provides a direct protective covering for the neural tissue and blood
vessels.
Together, these three layers of meninges form a protective system that helps cushion
and protect the central nervous system (brain and spinal cord) from mechanical
shocks and injuries. The space between the arachnoid mater and the pia mater is filled
with cerebrospinal fluid, which further contributes to the protection and buoyancy of
the central nervous system.
49. **What are the three struct
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49. **What are the three structures formed by the separation of the layers of the dura mater, and where are they located?**
Faix Cerebri:
• Location: Between the two halves of the brain.
• Description: It's like a vertical curtain separating the right and left sides of the
brain.
2. Tentorium Cerebelli:
• Location: In the back of the head.
• Description: Think of it as a tent dividing the upper part (cerebrum) from the lower
part (cerebellum) of the brain.
3. Faix Cerebelli:
• Location: In the back, but lower down.
• Description: Similar to the falx cerebri but separating the two halves of the
cerebellum.
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50. **Name three intracranial venous structures (sinuses) found between the layers of the dura mater.**
Superior Sagittal Sinus:
• Location: At the top, like a river along the upper part of the brain.
• Function: Drains blood from the upper part of the brain.
2. Transverse Sinuses:
• Location: Sideways, running on either side like rivers along the tent-like structure.
• Function: Collect blood from the upper part and carry it sideways.
3. Sigmoid Sinuses:
• Location: Curving down at the back of the head.
• Function: Collect and channel blood down, eventually connecting to the neck
veins.
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52. **Can you describe the circulation pathway of cerebrospinal fluid (CSF) through the ventricles and subarachnoid space?**
Production in Ventricles:
• CSF is made in the brain's ventricles,
2. Ventricular Flow:
It flows through ventricles, from lateral to third to fourth.
3. Into Subarachnoid Space:
• CSF exits into the space around the brain and spinal cord.
4. Down the Spinal Cord:
• Some goes down the spinal cord's central canal.
5. Absorption and Return:
• Excess SF gets absorbed back into the bloodstream through specialized
structures, completing the circulation.
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53. **What is the main purpose of the Blood-Brain Barrier, and where is it less effective?
The main purpose of the blood-brain barrier (BBB) is to protect the brain by selectivel
controlling what substances can enter. It maintains a stable environment for optimalneural
function. The BBB is less effective in certain regions called circumventricular organs,
allowing them to monitor blood for specific functions, like hormone regulation.
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How many ventricles are there in the brain, which one is located below the lateral ventricles
Lateral Ventricles (First and Second):
• Location: One in each side of the brain, like big pockets.
• Shape: Horseshoe-shaped, within the cerebral hemispheres.
2. Third Ventricle:
• Location: Below the lateral ventricles, in the middle.
• Shape: Slim and in the middle, between the thalami.
3. Fourth Ventricle:
• Location: Towards the back, between the brainstem and cerebellum.
• Shape: Diamond-shaped, leading down to the spinal cord.
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54. **How many lobes does each cerebral hemisphere have, and can you name them?
Each have 4 lobes
1. Frontal Lobe: At the front, involved in motor functions and higher cognition.
2, Partetal Lobe: Behind the frontal lobe, processes sensory information.
3. Temporal Lobe: On the sides, responsible for auditory processing and memory.
4, Occipital Lobe: At the back, main center for visual processing
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55. **Name the three main basal nuclei and their functions.**
Striatum (Caudate Nucleus and Putamen):
• Function: Controls voluntary movements and procedural learning.
2. Globus Pallidus:
• Function: Regulates voluntary motor movements in coordination with other
structures.
3. Substantia Nigra:
• Function: Produces dopamine for motor control; its dysfunction is linked to
Parkinson's disease
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56. **What are the three main components of the diencephalon, and what functions are associated with the hypothalamus?**
Thalamus:
• Function: Relay atatien for sensery infermatien te the cerebral cortex,
2. Hypothalamus:
Functiona:
Autonomle regulation,
Endocrine regulation,
• Body temperature regulation.
Emotional and behavioral responses
• Regulation of eireadlan rhythma.
• Control of food and water intake
3. Epithalamus:
• Function: Includes the pineal gland, preducing melatonin for aleep-wake cycles
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57. **Which part of the brain stem relays auditory and visual information, and what is the function of the medulla oblongata?**
Auditory and Visual Information Relay:
Part of the Brain: The thalamus relays auditory and visual information.
• Function: The thalamus acts as a relay station, transmitting sensory information,
including auditory and visual signals, to the cerebral cortex for further
processing and perception.
2. Medulla Oblongata:
• Function: The medulla oblongata is primarily responsible for vital autonomic functions, including:
• Regulation of heart rate and blood pressure.
• Control of respiratory functions (breathing).
• Reflex activities like coughing, sneezing, and swallowing.
• Coordination of various autonomic functions to maintain homeostasis.
The medulla oblongata is a critical part of the brainstem, connecting the spinal cord to the
brain. It plays a crucial role in controlling essential life-sustaining functions and serves as a relay center for certain reflexes.
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58. **Which regions is the spinal cord is larger?**
The spinal cord is not uniform in size throughout its length. The region of the spinal
cord that corresponds to the cervical enlargement is generally larger than other
regions. The cervical enlargement is located in the neck region (cervical spine) and is
responsible for providing innervation to the upper limbs. This enlargement
accommodates the increased number of neurons and nerve fibers needed for the
complex movements and control of the arms and hands.
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59. **Where does the spinal cord extend down to?**
The spinal cord extends from the base of the brain, specifically from the medulla
oblongata, and it runs down through the vertebral canal. The spinal cord typically
extends to the level of the first or second lumbar vertebra in adults. Beyond this point,
the spinal canal continues as the cauda equina, a collection of nerve roots resembling
a horse's tail, which extends further down the vertebral canal within the lumbar and
sacral regions.
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60. **What is the function of the cervical enlargement of the spinal cord?**
The cervical enlargement of the spinal cord is associated with the functions related to the
upper limbs, particularly the arms and hands. It is an expanded region of the spinal cord
located in the neck (cervical) region. The larger size of the cervical enlargement reflects
the increased number of neurons and nerve fibers needed to support the intricate motor
control and sensory input associated with the upper extremities.
1. Motor Control: Neurons in the cervical enlargement send motor signals to muscles in
the arms and hands, allowing for voluntary movements and fine motor control.
2. Sensory Processing: The cervical enlargement receives sensory input from the upper limbs,
conveying information about touch, temperature, pain, and proprioception
(awareness of body position in space).
3. Reflexes: The cervical enlargement is involved in generating reflexes that involve the muscles of the upper extremities. Reflex actions, such as withdrawing a hand from a
painful stimulus, are coordinated in this region.
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61. **Describe the appearance of the grey matter in the cross-section of the spinal cord.**
n a cross-section of the spinal cord on a CT scan or X-ray, grey matter appears as darker,
more radiolucent regions compared to the surrounding white matter. This is because grey
matter contains more cell bodies and less myelin, making it less dens and allowing X-rays
to pass through more easily.
The grey matter is typically seen in the shape of a butterfly or an "H" in the center of the
spinal cord cross-section. This configuration represents the distribution of grey matter,
which contains neuronal cell bodies and synapses. Surrounding the grey matter is the
white matter, which appears lighter due to its higher myelin content and denser structure,
restricting the passage of X-rays
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62. **What are the three columns in which white matter is divided?**
Dorsal (Posterior) Columns:
• Located posteriorly (towards the back) in the spinal cord.
• Involved in carrying sensory information, particularly proprioception, vibration, an
fine touch, from the peripheral nerves to the brain.
2. Lateral Columns:
• Situated on the lateral (side) aspects of the spinal cord.
• Contain both ascending and descending tracts involved in various sensory and
motor functions.
3. Ventral (Anterior) Columns:
• Found anteriorly (towards the front) in the spinal cord.
• Involved in transmitting motor signals from the brain to the peripheral nerves,
controlling voluntary muscle movements.
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63. **Explain the role of the dorsal column tract in the spinal cord.**
The dorsal column tract in the spinal cord carries sensory information from the skin,
muscles, and joints to the brain. It is crucial for transmitting sensations such as touch,
vibration, and proprioception, enabling us to perceive and interpret sensory input
accurately
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64. **How does the voluntary muscle movement pathway differ from involuntary movement in the spinal cord?**
Voluntary muscle movement
Involves upper motor neurons from the cortex and lower motor neurons in the spinal cord.
Allows conscious and precise control of skeletal muscles.
Involuntary muscle movement:
Often uses reflex arcs in the spinal cord
Involves interneurons for rapid, automatic responses without conscious thought.
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65. **How many pairs of cranial nerves are there?**
14
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66. **Name the cranial nerves involved in sensory functions.**
On - olfactory - sensory
Occasions - optics - sensory
Truck - trigeminal - both
Funny - facial - both
Very - vestibulocochlear - sensory
Good - glossopharyngeal - both
Vehicle - vagus - both
Some say marry money but my brother says big brains matter more
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67. **Which cranial nerve controls the diaphragm, and through which foramen does it exit the skull?**
The phrenic nerve (from spinal nerves C3-C5) controls the diaphragm. It exits the through
the jugular foramen.
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68. **How many pairs of spinal nerves are attached to the cord?**
31
1. Cervical Nerves (C1-C8): 8 pairs
2. Thoracic Nerves (T1-T12): 12 pairs
3. Lumbar Nerves (L1-L5): 5 pairs
4. Sacral Nerves (S1-S5): 5 pairs
5. Coccygeal Nerve (Co1): 1 pair
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69. **Which nerves make up the cervical plexus?**
1. Phrenic Nerve (C3-C5):
• Innervates the diaphragm and plays a crucial role in breathing.
2. Lesser Occipital Nerve (C2):
• Provides sensory innervation to the skin on the back of the head.
3. Greater Auricular Nerve (C2-C3):
Supplies sensory fibers to the skin over the parotid gland and the external ear.
4. Transverse Cervical Nerve (C2-C3):
• Innervates the anterior and lateral aspects of the neck.
5. Supraclavicular Nerves (C3-C4):
Divide into sensory branches providing innervation to the skin over the shoulder and upper chest
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70. **What is the significance of the phrenic nerve?**
e phrenic nerves are crucial for breathing as they control the diaphragm, the primary
muscle involved in inhalation. Damage or disruption to these nerves can lead to respiratory
difficulties, emphasizing their vital role in maintaining effective breathing.
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71. **What is the impact of a spinal cord injury at the C3 level?**
A C3 spinal cord injury can affect the muscles involved with breathing which, without immediate medical attention, can be fatal. This is because the primary muscle involved in respiration, called the diaphragm, is controlled by the C3-C5 spinal nerves.
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72. **Describe the effects of a spinal cord injury at the C6 level.**
A person with complete C6 SCI does not have the ability to move their trunk or legs. They have limited movement of the arms and should be able to move their shoulders, bend their elbows, and extend their wrists.
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73. **What does the term "dermatomes" refer to, and why is knowledge of dermatomes useful?**
Dermatomes are areas of skin on your body that rely on specific nerve connections on your spine.
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74. **What is the primary function of the autonomic nervous system?**
- outside of our control
- consists of sympathetic ( we want and need to use energy, nerves telling your body)
- parasympathetic (when its conserving energy, fight muscles are relaxed)
1. Heart Rate and Blood Pressure: The ANS adjusts heart rate and blood pressure to meet
the body's changing needs.
2. Respiration: It influences respiratory rate and depth to optimize oxygen and carbon
dioxide levels.
3. Digestion: The ANS modulates digestive processes, including stomach activity and
nutrient absorption.
4. Metabolism: It influences metabolic functions, including glucose regulation and energy
balance.
5. Temperature Regulation: The ANS helps regulate body temperature through processes
like sweating or vasoconstriction.
6. Detoxification: It plays a role in detoxifying the body by influencing processes like
urination and defecation.
7. Stress Response: The sympathetic division of the ANS initiates the "fight or flight"
response during stress, preparing the body for quick, intense action.
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75. **Name the regions of the brain that control the autonomic nervous system.**
Hypothalamus
The hypothalamus plays a central role in regulating and coordinating
autonomic functions, including responses to stress, emotions, and maintenance of internal
homeostasis.
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76. **Which limbic region is mentioned as having an influence on the autonomic nervous system?**
Anxiety, aggression, fear conditioning; emotional memory and social cognition. Regulates the autonomic nervous system via hormone production and release. Secondarily affects and regulates blood pressure, heart rate, hunger and thirst
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Cranial Bones
Parietal (2)
Temporal (2)
Frontal (1)
Occipital (1)
Ethmoid (1)
Sphenoid (1)
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Name the cranial nerves
On - olfactory
Occasion - optic
Our - oculometer
Trusty - trochlear
Truck - trigeminal
Acts - abducens
Funny - facial
Very - vestibuocochlear
Good - glossophranyeal
Vehicle - vagus
Any - accessory
How - hypoglossal
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Name which nerves are sensory, motor or both
Some - sensory
Say - sensory
Marry - motor
Money - motor
But - both
My - motor
Brother - both
Says - sensory
Big - both
Brains - both
Matter - motor
More - motor
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Name the muscles of the TMJ
masseter,
temporal
lateral pterygoid
Medial pterygoid
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32. **Name the four types of glia cells found in the central nervous system.**
astrocyte cells,
microglial cells,
shank cells, Ependymal
oligodendrocyte cells
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33. **What is the role of Schwann cells in the peripheral nervous system?**
The primary role of Schwann cells in the peripheral nervous system (PNS) is to provide support and insulation to nerve fibers. Here are the key functions of Schwann cells:
1. Myelination: Schwann cells produce a fatty substance called myelin, which wraps
around and insulates certain nerve fibers in the peripheral nerves. Myelination
enhances the speed and efficiency of nerve signal transmission.
2. Node of Ranvier Formation: Myelination by Schwann cells is not continuous; there are
small gaps between successive Schwann cells called Nodes of Ranvier. These nodes
allow for the rapid saltatory conduction of nerve impulses.
3. Nerve Regeneration: After injury to a peripheral nerve, Schwann cells play a crucial
role in the regeneration process. They guide and support the regrowth of damaged
nerve fibers, facilitating the reconnection of nerve cells and the restoration of function.
4. Nutrient and Waste Exchange: Schwann cells assist in the exchange of nutrients and
waste products between the nerve fibers and the surrounding extracellular fluid,
supporting the overall health of the peripheral nerves
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34. **Describe the structural features of a neuron.
formation of myelin sheath
Support and privation, modes of ranvier, nerve regulation, metabolic support
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35. **What is the function of the myelin sheath?*
insulated layer that wraps around the axon of PN.
Provides insulation allowing for faster
conduction of nerve impulses along the axon.
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Cerebrum
The cerebrum (front of brain) comprises gray matter (the cerebral cortex) and white matter at its center. The largest part of the brain, the cerebrum initiates and coordinates movement and regulates temperature.
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Circle of Willis
The circle of Willis, a loop of blood vessels near the bottom of the brain that connects major arteries, circulates blood from the front of the brain to the back and helps the arterial systems communicate with one another.
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Vertebral arteries
The vertebral arteries follow the spinal column into the skull, where they join together at the brainstem and form the basilar artery, which supplies blood to the rear portions of the brain.
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External carotid arteries
The external carotid arteries extend up the sides of your neck, and are where you can feel your pulse when you touch the area with your fingertips. The internal carotid arteries branch into the skull and circulate blood to the front part of the brain.
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Pineal gland
The pineal gland is located deep in the brain and attached by a stalk to the top of the third ventricle. The pineal gland responds to light and dark and secretes melatonin, which regulates circadian rhythms and the sleep-wake cycle.
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Hypothalamus
The hypothalamus is located above the pituitary gland and sends it chemical messages that control its function. It regulates body temperature, synchronizes sleep patterns, controls hunger and thirst and also plays a role in some aspects of memory and emotion.
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Pituitary gland
Sometimes called the “master gland,” the pituitary gland is a pea-sized structure found deep in the brain behind the bridge of the nose. The pituitary gland governs the function of other glands in the body, regulating the flow of hormones from the thyroid, adrenals, ovaries and testicles. It receives chemical signals from the hypothalamus through its stalk and blood supply.
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Temporal bone
Temporal lobe. The sides of the brain, temporal lobes are involved in short-term memory, speech, musical rhythm and some degree of smell recognition.
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Cerebellum
Cerebellum
The cerebellum (“little brain”) is a fist-sized portion of the brain located at the back of the head, below the temporal and occipital lobes and above the brainstem. Like the cerebral cortex, it has two hemispheres. The outer portion contains neurons, and the inner area communicates with the cerebral cortex. Its function is to coordinate voluntary muscle movements and to maintain posture, balance and equilibrium.
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Mid brain
Midbrain. The midbrain (or mesencephalon) is a very complex structure with a range of different neuron clusters (nuclei and colliculi), neural pathways and other structures. These features facilitate various functions, from hearing and movement to calculating responses and environmental changes.
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Pons
Pons. The pons is the origin for four of the 12 cranial nerves, which enable a range of activities such as tear production, chewing, blinking, focusing vision, balance, hearing and facial expression. Named for the Latin word for “bridge,” the pons is the connection between the midbrain and the medulla.
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Medulla
Medulla. At the bottom of the brainstem, the medulla is where the brain meets the spinal cord. The medulla is essential to survival. Functions of the medulla regulate many bodily activities, including heart rhythm, breathing, blood flow, and oxygen and carbon dioxide levels. The medulla produces reflexive activities such as sneezing, vomiting, coughing and swallowing.
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Medulla
Medulla. At the bottom of the brainstem, the medulla is where the brain meets the spinal cord. The medulla is essential to survival. Functions of the medulla regulate many bodily activities, including heart rhythm, breathing, blood flow, and oxygen and carbon dioxide levels. The medulla produces reflexive activities such as sneezing, vomiting, coughing and swallowing.
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Cerebral cortex
The cerebral cortex is divided into two halves, or hemispheres. It is covered with ridges (gyri) and folds (sulci). The two halves join at a large, deep sulcus (the interhemispheric fissure, AKA the medial longitudinal fissure) that runs from the front of the head to the back. The right hemisphere controls the left side of the body, and the left half controls the right side of the body. The two halves communicate with one another through a large, C-shaped structure of white matter and nerve pathways called the corpus callosum. The corpus callosum is in the center of the cerebrum.
