Exam 2 Flashcards
Common Chemicals in Chemical Synapse?
Neurotransmitters
Signal Propagation
Think Myelinated (motor function) vs Unmyelinated (tickle, heat, etc)
What are Chemical Synapses dependent on?
What Receptors are located on the receiving cell
What would a small, Unmyelinated Neuron be good for?
Tickles, Cold, Warmth (R side of Chart)
In a Neuron, how long is an Action Potential?
Milliseconds
Where are Oligodendrocytes located?
CNS
What is Striated per Lecture?
Skeletal Muscle
How many binding sites does nACh-R have?
2 binding sites; both have to be occupied simultaneously to work
Purpose of Schwann Cells
PNS Myelin Producing Cell
Overall Slower Cell Signaling?
Longer Nerve, Narrow Diameter, Decreased Insulation
What receptors are located on the Heart at the NMJ?
Muscarinic/ACh receptors
What is the main ion that goes through an electrical synapse? Why?
Na+, it is small and can fit
What makes cells more resistant to crush injuries?
Myelin; add layer of robustness
Where are Schwann Cells located?
PNS
What action potential does Dr. Schmidt give an example of?
Electrical Probes being placed
What is Myelin?
The insulation around a Neuron
What happens if there are increased gap junctions?
Decreased resistance for AP; easier for signals to be sent
What Happens if you take away Cl- permeability?
Increased Vrm –> Seizures
Purpose of Oligodendrocytes
CNS Myelin Producing Cell
Multiple Sclerosis (MS)
Myelin sheath is damaged in the motor system, so signals are not conducted properly
How does Cl- affect the cell?
Hyperpolarizes the cell; “brakes” on the NS
What are the Macroglial Cells?
Astrocytes, Ependymal Cells, Oligodendrocytes, Schwann Cells
Normal HR per lecture?
70-72 b/min
How does Atropine Work?
Blocks normal vagus activity on the heart; Increase HR
How do Baroreceptors adapt?
Desensitize to increase in MAP, and make it the new “normal”
What does an Axon do for a Neuron?
Sends signals; Myelinated
What is a Threshold?
It determines if the cell generates an action potential. Depolarization has to get above the threshold line in order to generate an action potential
Are Electrical Synapses 1 direction?
No, 2 Directions; good or bad; if rogue cell in heart, random electrical impulses
What is the Node of Ranvier?
The spaces between the Myelin Sheath that are packed with Fast Na+ channels
Why are they named Astrocytes?
“They look like a star”
Purpose of Pseudounipolar Neuron?
Majority of sensor cells outside of spinal cord; sensory function that relays to the NS
Are Chemical Synapses faster or slower than Electrical Synapses?
Slower
Where in the Pseudounipolar Neuron is a decision made?
The Sensor
Myelinated Neuron Letter?
“A”
What does the Soma on a Pseudounipolar Neuron do?
Make proteins and replace things that need to be maintained
What is a Connexon?
A tube/cylinder protein that is implanted in the cell to conduct signals to other cells attached
Which directions can an action potential go on a cell?
Bidirectional
What Ion is Permeable in the Axon Hillock?
Cl-; suppress the CNS
What signs are a result of Hypocalcemia?
Trousseau and Chvostek Signs
What does Hypercalcemia do to Motor Neuron Activity?
Under activity of the Motor Neuron; decreased muscle contractions
What does Increased Gap Junctions mean for the Action Potential?
Decreased resistance for AP, so faster
Why is an action potential longer in the heart?
It allows for the heart to contract and pump blood; in seconds
Why would it be pointless if excitatory on Axon Hillock?
It would bypass the rest of the cell and interrupt the whole reason for making decisions
Which Vagus nerve releases ACh to the AV node?
L Vagus Nerve
What is an easier nerve to block?
Nerves that are located outside of a nerve bundle (not buried)
How does ACh and K react to each other?
ACh opens K channels, causing them to leave (makes cell more -)
How did Dr. Schmidt describe a Ca++ ion?
“Big and Clunky”
What do Dendrites do?
Receivers on the Soma; usually not myelinated
Where is the SA node located?
L side of Heart
How does ACh behave in Skeletal Muscle?
Excitatory
What is Demyelination?
Progressive loss of Myelin over time
What Neurotransmitter is located on the Axon Hillock?
GABA
In the Heart, how long is an Action Potential?
Seconds
What does Somatic Sensation mean?
“Able to be Sensed”
Guillain-Barre Syndrome
A lot of people Post-Covid got this, as their antibodies they built up were reacting and attacking their nervous system
What happens to the Fast Na+ and K+ channels that are located under the Myelin Sheath over time?
They disappear over time
Where do Paralytics work?
NMJ
What are support tissues/cells called in the NS?
Glial Cells
How do Pressure and Stretch Sensors work?
When flat and stretched, increased Na+ coming in, so Action Potential tells you there is pressure
Which takes more Local Anesthetic to block? Why?
Myelinated Cell; the density of Fast Na+ channels
Fast Adapting Sensors
Squeeze a ball and forget about it over time b/c brain does not need all this information; NS is concerned about change;
Another name for Neuron Cell Body?
Soma
Are Electrical Synapses faster or slower than Chemical Synapses?
Faster
Location of Electrical Synapses?
Myocardium, Smooth Muscle, Some Neurons
Are Schwann Cells good or bad at regenerating Myelin?
Good
Locations of Electrical Synapses?
Smooth Muscle, Myocardium, some Neurons
How many projections do Bipolar Neurons have?
2
Be Able to Label a Typical Neuron
Soma, Dendrite, Axon, Axon Hillock, Presynapsis, Postsynapsis, Myelin Sheath, Nodes of Ranvier
Normal MAP per lecture?
100 mmHg
What happens if Baroreceptors do not adapt?
If MAP jumps from 100 mmHg to 200 mmHg, without adaptation, then an action potential cannot fire any faster. This limits brain activity to get information from this high BP
Increased pressure = ? Na+ influx
Increased
What is Saltatory Conduction?
The Action Potential moving down a Myelinated Neuron
Where are Dendrites located?
Sticking out of the Soma
Purpose of Microglia Cells
Immune System in CSF cells; Macrophage that eats dead cells and clear up debris
What Ion is the “brakes” of the nervous system?
Cl-
What is Myelin derived from?
Sphingomyelin
Purpose of Multipolar Neuron?
Motor Neurons; Decision Making Cells (decides whether to fire an action potential or not)
Where is AV node located?
Top of Septum in Heart
What is very energy effecient?
Myelinated Neurons
Calcium Channels can also be called what?
L-Type channel
Important example of ADAPTATION?
Baroreceptors
How does Mg+ work in the cell?
Similar to Ca++; hyperpolarizes the cell; reduces electrical activity of the cell (heart)
Lightly Myelinated Neuron Letter?
“B”
Which Neuron Type is considered the “decision making cell”?
Multipolar Neuron
Examples of Pressure and Stretch Sensors?
Pacinian Corpuscle, Meissner’s Corpuscle
Brain tumors are called __?
Glial Tumors
What is an Axon Hillock?
Beginning of an Axon; GABA mediated to suppress electrical activity in the CNS
What will an antimuscarinic do to the heart?
Increases HR; closes K+ channels, which makes cell more (+)
Neuron Action Potential Pathway
Brain/SC - Motor Neuron - Action Potential - Neurotransmitter released at NMJ
How does ACh behave in the Heart?
Inhibitory
What shape is nACh-R?
Doughnut shaped (-) charged; attracts (+) Na to start AP
Without the Nervous System, what would be the normal HR per lecture?
110 b/min
What Does Myelin Sheaths do to Na+ channels?
Blocks the Na+ channels, sending Na+ down the line to the Nodes of Ranvier
Motor Neurons need a ? to talk to skeletal muscle?
Neurotransmitter
What does Myelin help the cell?
Increased protection, saves energy by blocking the NaKATP pump, speeds up signal transduction
Are Oligodendrocytes good or bad at regenerating Myelin?
Bad
Non-Myelinated Neuron Letter?
“C”
How long does it take a Baroreceptor to adapt?
2 days (slow)
What does Massive Vagus Stimulation do to the HR?
Slows HR, b/c causes Hyperpolarization
When you lose Myelin, what happens to the NaKATP pumps?
The continuously pump Na+ like normal, but since nothing to keep them in, will never reach the Node of Ranvier; signal will not be sent (paralysis)
What does Decreased Gap Junctions mean for the Action Potential?
Increased resistance for AP, so slower
How many Connexins make a Connexon?
6
Overall Faster Cell Signaling?
Shorter Nerve, Wider Diameter, Increased Insulation
What happens if you lose Myelin in your CN2 or Retina?
Blind or trouble seeing
What happens if there are decreased Gap Junctions?
Increased resistance for AP; some places in heart do this intentionally to pause/delay
What would a Big,Myelinated Neuron be good for?
Motor Neuron; Left side of Chart
What structures are included in the CNS?
Optic Nerve (CN2), Retina, Brain, Spinal Cord
Where is Muscarine found, per lecture?
Rainforests
What makes a cell less prone to ischemia?
Myelin
Per lecture, how many neurons can a neuron connect with?
10,000 (all connections influence what the cell does)
Is an Action Potential a (-) or (+) feedback?
(+) feedback
Example of Bipolar Neuron in the body?
Photoreceptors in the Optic Nerve and Retina
Where do Paralytics work?
NMJ
Purpose of Bipolar Neuron?
SPECIALIZED Senses; sense info and sends to NS
What Does Hypocalcemia do to Motor Neuron Activity?
Increased Na+, as it does not block the leaky Na+ channels; Increases Motor Neuron Activity (increased muscle activity)
Is Electrical Synapse diffusion or active transport?
Simple Diffusion
Which receptor suppresses electrical activity in the heart?
mACh-R
3 Types of Neurons?
Multipolar, Pseudounipolar, Bipolar
When a cell is flattened, what happens to the Fast Na+ Channels?
They are increased, which increases action potentials
What does ACh effect in the heart?
Pacemaker activity of heart (70-72 b/min)
What is a Free Nerve Ending?
Pain Sensor
What is in the Soma of a Neuron?
Nucleus, mitochondria, etc
If the Nervous System does not need 100 million neurons, what will it do?
Try to get rid of the ones it does not need
What part of the Astrocyte binds to the endothelial cells/capillary?
Astrocytic Infoot
How does Ca++ help in Hyperkalemia?
Ca++ will block Na+ permeability, making the Cell more (-); if the cell is more (-), will pull in K+ ions
Purpose of Ependymal Cells
Produce CSF; moves it downstream via cilia to circulate
What is another name for a Free Nerve Ending?
Nociceptor
Purpose of Golgi Tendon Apparatus?
On skeletal or smooth muscle to let body know how muscles are doing and moving
4 Causes of Demyelinating Diseases?
Genetics, infection, autoimmune, polyneuropathies
What happens if an alcoholic stops drinking?
GABA is not released anymore, so crazy CNS involvement; Increased +, so seizures and DTs
What happens to an action potential when there is an increased strength of a stimulus?
Increased action potential speed
What happens to Na+ when the cell is flattened/widened?
Increases the amount of Na+ channels, which increases amount of action potentials
What do 2 Connexons make?
Gap Junction
What are included in the PNS?
Everything outside of the Spinal Cord
Which Vagus nerve releases ACh to the SA node?
R Vagus Nerve
What is Dihydropyridine (DHP)?
A class of CCB, specifically for smooth muscle and heart. Vasodilator with little effect upon cardiac contractility
Purpose of Astrocytes
BBB support; maintain/buffer electrolyte balance within CNS (CSF);wrapped around BBB tight junction and capillaries
What are the subunits of “A”? - Order largest to smallest
Alpha, Beta, Gamma, Delta
Alcohol is a __ Agonist?
GABA
Superior
Head (top)
Inferior
Feet (bottom)
Dorsal
Back (posterior); fin of a dolphin or shark
Ventral
Front (anterior)
Anterior
Front
Posterior
Back
Medial
Middle
Lateral
Side
Rostral
Front and Upper (think Beak of a Bird)
Caudal
Lower and Rear (Tail of a Bird)
Distal
Further from NS
Proximal
Closer to NS
CNS Divisions: 4 Parts
Superficial
Closer to skin
Deep
Deeper in skin
Sagittal
Cut from L to R side of body (median); line right down the middle
Coronal
Cut Anterior to Posterior
Horizontal
Cut Superior to Inferior (head to feet)
Oblique
“Goofy or Odd Angle”
CNS: Telencephalon
The cerebral hemispheres or cortex; the upper and outer part of the brain
CNS: Diencephalon
The more inner part; middle between the Telencephalon and Brain Stem
CNS: 3 parts of Brainstem
Midbrain, Pons, Medulla Oblongata
Another name for Telencephalon?
Cerebral Hemispheres
Another name for Midbrain in Brain Stem? Location?
Mesencephalon; top of Brain Stem
Shape of Pons in Brain Stem? Location?
Olive Shaped Structure;
Lowest Level of Brain Stem?
Medulla Oblongata
What is a Sulcus?
It is a “groove” on the brain
What is a Gyrus (Gyri)?
“Lump” on brain; lumps of neurons and tissue
What is a Fissure?
“Really Deep Groove”
What do Grooves separate?
Groups of Tissue
What does the Frontal Lobe do?
It is the Thinking System of the brain; also, when you are “thinking to yourself”
What are the 4 Major Lobes?
Frontal, Parietal, Occipital, Temporal (separated by Sulci/Grooves)
What does the Parietal Lobe do?
Somatosensory (pain); located behind (posterior/dorsal) to the Frontal Lobe
Where is the Parietal Lobe in location to the Frontal Lobe?
Posterior/Dorsal
What does the Occipital Lobe do?
Vision processing and visual cortex; dorsal/posterior to Frontal
Where is the Occipital Lobe in relation to the Frontal Lobe?
Dorsal/Posterior
What does the Temporal Lobe do?
Auditory processing; located on Lateral side; “language listening and determining who is singing the song”
Major Landmarks in the Brain Divisions?
Central Sulcus and Temporal/temporolateral Fissure
What is the main anatomical marker when dissecting a brain?
The Central Sulcus
Why is the Temporal Fissure Important?
It separates the Temporal Lobe from the Frontal/Parietal Lobes
Why is the Precentral Gyrus Important?
It is the Primary Motor Cortex
Where is the Precentral Gyrus in relation to the Frontal Lobe?
It is Posterior to the Frontal Lobe
Why is the PostCentral Gyrus important?
It is the sematosensory portion of the parietal lobe
Where is the PostCentral Gyrus in relation to the Central Sulcus?
It is Posterior to the Central Sulcus
Why is the Longitudinal Fissure Important?
It separates the Left and R hemispheres
What does the Corpus Callosum do?
Cross Talk Communication between both sides of the brain
Where is the PreCentral Gyrus in relation to the Central Sulcus?
It is Anterior to the Central Sulcus
Why is the Corpus Callosum a lighter color on the diagram, per lecture?
It shows that it has a lot of myelinated neurons for cross talking
Per lecture, how do you expose the Corpus Callosum on the brain diagram?
Cut it in half with a saw
Per lecture, where does a concussion damage the brain?
Damages the gray areas of the brain; leads to decreased process in that area
What is the CSF a buffer between?
The Brain and the Cranium
Where is Gray Matter in relation to White Matter?
Superficial (closer to the cranium)
Where is White Matter compared to Gray Matter in the brain?
Deep to Gray Matter
Why is it easy to get blood flow to the Gray Matter?
The blood vessels are on the outside, so close in proximity to the Gray Matter
Why is Broca’s Area important?
The act of speaking and thinking about word formation/speaking is done here
Why is Wernicke’s Area Important?
Area where language comprehension is processed
Why is the Motor Cortex Important?
It is the primary acting on the action of motor functions
Why is the Limbic System Important?
It is the Emotional responses
Where are the Motor Plans Executed?
Back of the Frontal Lobe (Posterior, Dorsal)
Where are the Motor Plans Thought of?
Front of the Frontal Lobe (Anterior, Ventral)
What is White Matter?
Myelinated; generally axons; not many cell bodies; important for SENDING AND RECEIVING DECISIONS
T or F: The Spinal Cord does not have reflex decision making or problem-solving abilities
False
What is Gray Matter?
Unmyelinated; Butterfly shape; axons and dendrites; important for DECISION MAKING CENTER
Is Gray Matter Myelinated or Unmyelinated?
Gray Matter is Unmyelinated
Is White Matter Myelinated or Unmyelinated?
White Matter is Myelinated
What is the Anterior White Commissure (X-Over)? (AWC)
White portion of the spinal cord cross section that allows for signals to get from the L–> R side of the spinal cord (vice versa)
What shape is Gray Matter?
Butterfly shape
Describe the Posterior Median Sulcus
Really deep but narrow
Why is there a color difference in White and Gray Matter?
The myelination shows as a lighter color
Describe the Anterior Median Fissure
Wider (has an artery to wedge inside)
What are the 2 parts of Gray Matter?
Dorsal Horns and Ventral Horns
What are Dorsal Horns?
In the back of Gray Matter; have cell bodies on it; used for SENSORY
What are Ventral Horns?
In the front of Gray Matter; has cell bodies on it; used for MOTOR FUNCTION
Which access is easiest to get to the Dorsal Horns of Gray Matter?
Superficial Approach (epidurals, spinals)
Which way does information get into the Gray Matter?
Comes in from a horizontal direction, then jumps from Dorsal to Ventral horns
What is the Central Canal?
The center part of the gray matter that is responsible for producing the CSF and moving it down the Spinal Cord
What Surrounds the Central Canal?
Lamina 10
What Cells are in the Central Canal?
Ependymal Cells (CSF producing and Cilia moves it)
Lamina 10
The Gray Matter L and R side of cord connection; surrounds the Central Canal; made of Commissures
What is the Lateral Horn (Visceromotor)?
Random horn Dr. Schmidt pointed out in lecture
What is the Anterior Approach to blood supply in the Spinal cord?
Intercostal Arteries
What is the Posterior approach to blood supply in the Spinal Cord?
Upper Neck and Brain Stem
A Spinal Nerve is __ + __?
Posterior Rootlets + Anterior Rootlets
What functions do Spinal Nerves contain?
Sensory and Motor Function
Where are Posterior Rootlets attached?
Dorsal Horns
Where are Anterior Rootlets attached?
Ventral Horns
What are Posterior Rootlets used for?
SENSORY FUNCTION
What are Anterior Rootlets used for?
MOTOR FUNCTION
Where do all the Posterior Rootlets meet at?
The Posterior Root
Where do all the Anterior Rootlets meet at?
The Anterior Root
What is the Spinal Ganglion?
Where the big collection of cells on the posterior root side congregate
What type of Neurons are located on the Spinal Ganglion? Why?
Pseudounipolar Neurons; these are the sensory neurons so help with sensory signals being sent up the posterior side (to the Dorsal Horn)
What is the Primary purpose of the Descending Spinal Tract?
Motor Response
What is the Primary Purpose of the Ascending Spinal Tract?
Sensory
5 sections of the Spine?
Cervical, Thoracic, Lumbar, Sacral, Coccygeal
How many Vertebrae are located within the Cervical Region?
7 vertebrae
How many Pairs of Spinal Nerves are located within the Cervical Region?
8 spinal nerve pairs
Where are the spinal nerve pairs in the Cervical region compared to the location of the Cervical Vertebrae?
The 1st 7 pairs are above their vertebrae; the 8th is below the 7th vertebrae, setting up for the rest of the vertebrae and their nerve pairs
How many vertebrae are in the Thoracic region?
12 vertebrae
How many vertebrae are in the Sacral region?
5 vertebrae
How many spinal nerve pairs are in the Thoracic Region?
12 nerve pairs
How many Vertebrae are in the Lumbar region?
5 vertebrae
How many spinal nerve pairs are in the lumbar region?
5 spinal pairs
How many spinal nerve pairs are you born with in Coccygeal?
2, combine to 1 as you grow older
How many pairs of spinal nerves are in the sacral region?
5 pairs of spinal nerves
How many spinal nerve pairs are in the Coccygeal region?
1 pair
Where are the spinal nerve pairs located in relation to the vertebrae (excluding cervical spine)?
they originate under their vertebrae
What are Dermatomes? Dermatome Man?
The regions of the body split up by spinal nerves; the guy bend over with different colored regions of nerves
From a frontal view, what kind of curve is Thoracic Kyphosis?
Concave Curve
What are C2,C3 for?
Sensors for head and neck
What is Cervical Lordosis?
A natural occurring anterior curve of the neck
From a frontal approach, what kind of curve is Cervical Lordosis?
Convex Curve
What is Thoracic Kyphosis?
A natural posterior curve; if increased, leads to “hunchback”
What is Sacral Kyphosis?
A natural posterior curve
From a frontal view, what kind of curve is Sacral Kyphosis?
Concave curve
What is Scoliosis? What type of curve?
The lateral curvature of the spine; L–R; abnormal
What is Kyphotic Curvature?
Outward curve to force concave curve (from the front)
What is Lordotic Curvature?
Inward curve to force convex curve (from the front)
Is pathologic Lordosis normal or bad?
BAD
Is pathologic Kyphosis normal or bad?
BAD
What shape is the spine normally, per lecture?
“S” shaped
What is the most common abnormal curvature?
Kyphoscoliosis
What curvature are we born with? Which one do we develop as we get older?
We are born with kyphotic curves (thoracic); as we grow older, we develop Lordotic curves (cervical)
What is considered “hunchback”?
Increased Thoracic Kyphosis (think old ladies)
Why can a baby not hold their head up?
They do not have Cervical Lordosis yet; to be developed
What is Lumbar Lordosis?
A natural anterior curve
From a frontal view, what type of curve is lumbar lordosis?
Convex curve
What is the Vertebral Body of the Vertebrae?
the weight supporting part of the vertebrae; intervertebral discs sit on this
What are the 2 parts of the Vertebral Branch?
the Pedicle and the Lamina