Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Comparative Vertebrate Anatomy > Test 2: Nervous System > Flashcards

Test 2: Nervous System Flashcards

1
Q

Name the major divisions of the nervous system, both anatomical and functional

A

Anatomically - Central and Peripheral NS
Functionally - Sensory and Motor of the PNS

Both sensory and motor divisions have somatic and visceral divisions

The visceral motor divison can be further divided into sympathetic or parasympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the primary functions of the nervous system?

A

Receiving sensory input

Monitoring internal and external stimuli

Integrating information

Processing sensory input and initiating response

Controlling muscles and glands

Works with endocrine system to control all other organs

Maintains homeostasis

Establishes mental activity

Consciousness, thinking, memory, emotion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the organs of the Central Nervous System?

A

Brain and Spinal cord in the dorsal cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the organs of the Peripheral nervous system?

A

All nervous tissue outside brain and spinal cord; nerves, ganglia, enteric plexus, sensory receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the divisions of the PNS?

A

Somatic Nervous System

Autonomic Nervous System

Enteric Nervous System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the divisions of the Somatic Nervous System

A

Somatic Afferent (sensory) - convey information from sensory receptors towards the CNS

Somatic Efferent (motor) - convey information away from the CNS towards skeletal muscles under voluntary control

Interneurons connect the two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the divisions of the Autonomic Nervous System

A

Sensory neurons convey information to sensory receptors primarily in visceral organs, involuntary

Two branches:

Sympathetic division - (fight-or-flight): dilates pupils, inhibits saliva, raises heart rate, halts digestive organs, relaxes bladder

Parasympathetic division - (rest-and-digest): constricts pupils, increases saliva, reduces heart rate, stimulates digestive organs, constricts bladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the Enteric Nervous System

A

Used to be grouped with the autonomic nervous system, brain of the gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Briefly describe the organization of the PNS with regards to neurons

A

Receptor -> sensory NS -> CNS -> motor NS - Effector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are neurons? What are their universal properties?

A

Nerve cells in the CNS and PNS

Receive stimuli and transmit action potentials

Three Universal properties:

1) Excitability: response to stimulus (environmental changes)
2) Conductivity: Neuronal response to stimulus is production
3) Secretion: When the signal reaches the synapse a neurotransmitter is scereted and crosses the cleft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe Neuroglia

A

Helpers that do not generate or connect nerve impulses, but support and maintain neural networks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

List the Neuroglia of the CNS

A

Astrocytes, Oligodendrocytes, Ependymal, Microglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

List the Neuroglia of the PNS

A

Satelitte cells, Schwann cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe Astrocytes

A

In the CNS

Maintain BBB, provide structural support, regulate ion/nutrient/chemical concentrations

Absorb and recycle neurotransmitters

Form scar tissue

Have foot processes that cover surface of neurons and pia mater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe Oligodendrocyes

A

In the CNS

Myelinate CNS axons

Wraps around a bunch of axons at once, limited regenerative capcitiy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe Ependymal cells

A

In the CNS

Line ventricles of brain and central canal of spinal cord

Produce and maintain cerebrospinal fluid

have cilia that help move fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe Microglia

A

In the CNS

Remove cell debris, pathogens, waste by phagocytosis

Similar to macrophages, responds to inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe Satellite cells

A

In the PNS

Surround neuron cell bodies, regulate nutrient and neurotransmitter levels around neurons in ganglia

Surrounds and insulates nerve soma

Similar to astrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe Schwann cells

A

In the PNS

Surrounds axons, responsible for myelination of peripheral axons

Participate in repair process after injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What’s the purpose of myelination?

A

Lets the electrical signal skip across the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the structure of myelin in the PNS

A

Neurilemma - thick outermost coil of myelin sheath that contains nucleus and most of cytoplasm of Schwann cells

Basal lamina - basement membrane that surrounds myelin sheath, Schwann cells

Endoneurium covers basal lamina, thin exterior layer of fibrous connective tissue (collagen and elastin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Myelination in the CNS

A

Oligodenrocyte wraps around multiple axons, but multiple are needed to cover each fiber

Starts 14 weeks after fertilization, breast milk is important for development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the segmented properties of the Myelin sheath

A

Nodes of Ranvier are gaps between segments

Internodes are the myelin covered segments

Initial segment is the short secition of nerve fiber between axon hillock and 1st glial cell

Trigger zone is the axon hillock and inital segment, role in initating nerve signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

White matter vs gray matter; function and structure

A

White matter is formed from aggregations of myelinated axons

Gray matter lacks myelin, is formed from neuronal cell bodies and dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Anatomy of a neuron, organelles
Dendrites - highly branches structures that receive signals and conudcts impulses toward Soma more dendrites = more information Soma is control center, contains a nucleus, nucleolus, cytoplasm, lysosomes, golgi complex, has extensive RER granules called Nissl bodies which produce neurotransmitters Cytoskeleton of microtubules and actin, lots of stuff traveling thorugh Axon conducts impulses away from cell body
26
Parts of an axon, named portions
Axoplasm - cytoplasm Axolemma - membrane of axon Enclosed by Schwann cells and myelin sheath Axon hillock is space between axon and soma Initial segment is beginning of axon Trigger zone is site where action potentials are generated; axon hillock and part of axon nearest cell body Axon terminal is full of neurotransmitters, sometimes swells into synaptic end bulbs
27
List the types of neurons, anatomically
Multipolar, bipolar, unipolar, anaxonic
28
List the types of neurons, physiologically
Afferent, efferent, interneuron could also be classfied by secretion of neurotransmitter
29
Describe a multipolar neuron
Has several dendrites and only one axon, located within brain and spinal cord, most common
30
Describe a Bipolar neuron, what are they used for
Have two rows coming off, the dendrite has just one row before it branches One main dendrite and one axon Used for special senses: sight, smell, hearing, balance retina, eye, inner ear, olfactory area of brain
31
Describe a unipolar neuron
has one axon that extends from body and divides, goes both directions, functions as both axon and dendritic root depending on direction touch or stretching
32
Describe an Anaxonic neuron
many dendrites but no axon No action potentials Helps in visual processes
33
Describe the factors behind conduction speed
Fiber diameter and presence of myelin, temperature also plays a role Larger fibers have more surface area and conduct signals more rapidly Myelin further speeds conduction Different areas need different speeds
34
How many cranial nerves and spinal nerves are there?
12 pairs of cranial nerves, 31 pairs of spinal nerves
35
What is necessary for the regneration of nerve fibers
Soma is intact Some neurolemma remains Nerve growth factor
36
What happens to the portion of the nerve fiber distal to the injury during regeneration?
It degenerates
37
Describe the general steps with regeneration of a nerve fiber?
Normal nerve fiber is cut - degerantion of distal portion, muscle wasting Regrowth - schwann cells, regeneration tube Late regeneration - Regeneration tube guides axon
38
Describe in detail what happens when a normal nerve fiber is cut
without new proteins distal portion degenerates Macrophages clear debris Muscle wasting Soma gets swollen as it can't send its signals Nerve growth factor from target cells ceases, must find new source
39
Describe in detail what happens in the regrowth step of nerve regeneration
Schwann cells come in, produce cell adhesion molecules and nerve growth factor Regeneration tube forms from schwann cells, basal lamina, neurilemma
40
Describe in detail what happens during the late regeneration stage of nerve fiber regeneration
Regeneration tube guides growing axon sprout back to synapse and target cell The nerve is unlikely to innervate the same muscle fiber in the same way, likely attaches to another one Soma shrinks to its original size, reinnervated fibers regrow
41
Describe Nerve Growth Factor
Protein secreted by glands, muscles, glial cells that binds to receptors on axon terminals Prevents apoptosis in growing neurons Enables growing neurons to make contact with their target cells Rita Levi-Montalcini isolated in 1950s
42
What are the two possible types of signals a neuron can communicate with?
Graded potentials/local potentials and action potentials
43
Compare a graded potential with an action potential
Graded potentials / Local Potentials- Short-distance communication; signals from dendrites Reversible, graded Can be either excitatory or inhibitory, if the graded potential is high enough to make it to the trigger zone an action potential occurs down the axon Action potentials- Long-distance communication Non-reversible Occurs if the graded potential is high enough
44
List the steps of an action potential
The resting membrane potential is the level at which the neuron normally sits at. 1) The local potential rises as Na+ slowly depolarize the membrane 2) Threshold is at -55mv, once the threshold is reached voltage-regulated Na+ gates open rapidly, all or none 3) Depolarization of membrane produces a spike in voltage, Na+ gates close as potential passes 0 mV, K+ gates start to open slowly 4) Peak at 35 mV 5) Repolarization as K+ leaves neuron to drop membrane potential back toward RMP 6) Hyperpolarization as K+ stay open long enough to drop potential slightly below RMP 7) Return to RMP 8) Refractory periods
45
Describe the two refractory periods
Absolute - voltage gated na channels are open, K channels are open, na channels are inactivating Relative - voltage gated k channels are still open, na channels are resting
46
Where are the channels needed for an action potential to occur?
Voltage gated are found on axon and axon hillock, needed for action potential Very few in myelin covered regions, many in nodes of Ranvier - Fast Na+ diffusion occurs between nodes - Saltatory conduction is the signal jumping from node to node
47
How does the body determine perception of stimulus or extent of response
Frequency of neuron firing, number of neurons recruited
48
Describe the three types of Fibers
A Fibers -Large, fast, myelinated neurons that carry touch and pressure sensations; many motor neurons are also of this type B Fibers -Medium size and speed, myelinated visceral sensory and autonomic preganglionic neurons C Fibers -smallest and slowest
49
Structure of a synapse
Presynaptic neurons have synaptic vesicles containing neurotransmitter Postsynaptic neurons have receptors and ligand-regulated ion channels
50
Chemical conduction at a neuron synapse
Calcium converts electrical signals into protein signals, vesicles release their neurotransmitters into synapse, Ligand gated channels on other side
51
Excitatory and inhibitory neurotransmitters
Both excitatory and inhibitory neurotransmitters are present in the CNS and PNS Same neurotransmitter may be excitatory in some locations and inhibitory in others Ex: ACh is released by many PNS neurons, excitatory at some locations and inhibitory in others
52
Integration
Integration is the process of combining excitatory and inhibitory inputs and responding accordingly Occurs repeatedly as interneurons are activated in higher parts of the brain (thalamus, cerebral cortex)
53
Four major parts of the brain
Brainstem, Cerebullum, Diencephalon, Cerebrum
54
Describe the brainstem, subsections
Containuation of spinal cord with different anatomy and physiology Medulla oblongata, pons, midbrain, reticular formation
55
Describe the Medulla oblongata
Contains all ascending and descending tracts between spinal cord and cerebrum Regulates mandatory body functions - Cardiovascular center - Respiratory rhythmicity center - Vomiting, coughing, sneezing centers
56
Describe the Pons
Directly above medulla, connects spinal cord with brain Breathing (inhalation and exhalation)
57
Describe the Midbrain
Hard to see without dissection, above pons Contains: Red nucleus -Voluntary movements Cerebral aqueduct for CSF formation and circulation (ependymal cells) Superior and inferior colliculi -Visual auditory reflexes Substantia nigra - Produces L-dopa -\> dopamine - Parkinson's association
58
Describe the Reticular formation
Dorsal to rest of brainstem Reticular activating system is the ascending portion - Sensory axons project to cerebral cortex - Coordinates what goes where, filters out insignificant information - Maintains consciousness, wake, alertness, sleep
59
Describe the Cerebellum
“Little Brain”, second largest part Posture, equilibrium, balance
60
What three things make up the Diencephalon
Thalamus, Epithalamus, Hypothalamus
61
Describe the function of the thalamus
Pain, sleep, temperature, pressure is related to thalamus en route to cerebral cortex Conjunction with attendant memories and emotions evoked
62
Describe the function of the epithalamus
secretes melatonin; sleep and biological clock
63
Describe the function of the hypothalamus
Controls homeostatic functions - Autonomic nervous system - Coordinates between NS and endocrine system - Body temperature - hunger/thirst - Internal clock
64
Describe the cerebrum
Largest part Consists of external gray matter cerebral cortex, internal cerebral white matter, and gray matter nuclei deep within white matter Mountains: gyri, Valleys: Sulci, Canyon: Fissure Integration of senses with behavior Longitudinal fissure separates into right and left hemispheres Central sulcus divides anterior frontal lobe from parietal lobe Occipital, parietal, frontal, temporal lobe
65
Describe the dentate gyrus
part of hippocampal circuit, thought to contribute to formation of new memories in spontaneous exploration of novel environments
66
Describe the hippocampus
Learning and memory, partially affected in alzheimers
67
Describe the cranial meninges, list them
Continues with spinal meninges Mirror their structure and function Anchors the brain in space Dura, arachnoid, and pia mater
68
Dura mater
tough outer layer external periosteal layer, internal meningeal layer dense irregular connective tissue, similar to skin surrounds and supports venous channels carry blood toward the brain
69
Arachnoid mater
spidery, elastic (dense connective tissue) Subarachnoid space is filled with cerebrospinal fluid
70
Pia Mater
thin and delicate
71
Blood Brain Barrier
Simple squamous vascular endothelium Astrocytes Tight junctions Oxygen, CO2, Water, lipid soluble freely enter and leave CNS; not water soluble Some travel across through active transport
72
Cerebral Spinal fluid, 3 Properties
Clear, colorless, produced by ependymal cells Circulates through brain ventricles and spinal cord and flows over and around the brain and cord in the subarachnoid space 1) Mechanical protection Brain floats in it, CSF absorbs shock 2) Homeostatic PH affects bloodflow, etc 3) Circulation Medium for nutrient and waste transportation
73
Cranial Nerve I
Olfactory
74
Cranial Nerve 2
Optic
75
Cranial Nerve III
Oculomotor
76
Cranial Nerve IV
Trochlear
77
Cranial Nerve V
Trigeminal
78
Cranial Nerve VI
Abducens
79
Cranial Nerve VII
Facial
80
CNVIII
Vestibulocochlear
81
CNIX
Glossopharyngeal
82
Cranial Nerve X
Vagus
83
Cranial Nerve XI
Spinal Accessory nerve
84
Cranial Nerve XIII
Glossopharyngeal nerve
85
Multiple sclerosis
Oligodendrocytes and mylein sheaths in the CNS deteriorate Nerve conduction disrupted Autoimmune disease, BBB breaks down and macrophages come into nerves tissue, destroys myelin
86
Tay-Sachs disease
Hereditary disorder Abnormal accumulation of glycolipid called GM2 in myelin sheath Blindness, loss of coordination, dementia Fatal before age 4
87
Leu Gehrigs Disease or ALS
Similar to CET Correlated to concussions, high contact sports Nerve fiber dyes, waste of skeletal muscle
88
Alzheimers Disease
100,000 deaths a year Memory loss, moody, combative, Deficiences of ACh and nerve growth factor Buildup of B-amyloid plaques
89
Parkinsons
Loss of motor function with no recovery Degeration of dopamine releasing neurons Treatment is L-dopa
90
Brain tumors
Tumors are masses of rapidly dividing cells Interfere with circuitry Difficult to treat with BBB Gliomas are malignant and rapid growth
91
Einsteins brain, theories of intelligence
Theory 1: More glial cells Theory 2: Less pronounced Corpus callosum, left and right brain friends
92
Serial killer brain, theories
Theory 1: Frontal lobe abnormality, less active Theory 2: Takes multiple parts, orbital cortex involved in ethics and decision making; Warrior gene MAO-A that regulates serotonin; funky childhood
93
Belief in God, brain activity
Religious people have increased activity in frontal lobe and language areas when in prayer, praying to god is similar to talking to people Thinking about god alters neural circuitry
94
Chapman’s Protocol
Sodium pentothal - first used, renders someone unconscious Pancuronium bromide - paralyzing agent, arrests breathing Potassium chloride - lowers resting electrical potential, stops heart
95
Spinal Cord motor vs sensory tracts location
More motor tracts superior, more sensory tracts inferior
96
Spinal meninges
Dura mater - encloses entire cord Arachnoid mater - delicate, avascular, attached to dura and forms roof of subarachnoid space where CSF circulates Pia mater - deepest, transparent, filled with blood and nutrients
97
Epidural space
between the dura mater and more superficial ligamentum flavum Epidural anesthesia has a needle placed between bones of posterior spine until it penetrates the ligamentum yet remains superficial to dura mater
98
Subdural space
Between dura and arachnoid Potential, dura and arachnoid firmly attached
99
Lumbar puncture
a needle inserted into the subarachnoid space to withdraw CSF and diagnose or reduce pressure Typically around L3,L4; below spinal cord
100
Two enlargements of spine
Cervical area C4 - T1 Motor output and sensory input to/from arms Lumbar area T9 - T12 Motor output and sensory input to/from legs
101
Roots
Bundles of axons that connect spinal nerve to cord Posterior root ganglion contain sensory neurons ganglion is a group of cell bodies Anterior root contains motor neurons
102
Gray and white matter, spinal cord
Gray matter is interior in butterfly shape, integration of IPSPs and EPSPs Anterior (larger wings), Posterior, Lateral gray horns White matter contains major sensory and motor tracts Anterior and posterior lateral columns
103
Central canal
entire length of cord down the center, filled with CSF
104
Tracts
Tracts are bundles of neuronal axons all traveling to the same place. PNS Names combine words that denote origin and ending place
105
Spinothalamic tract
spinal cord to brain, afferent tract sensations of pain, warmth, coolness, itching, tickling, deep pressure
106
Corticospinal tract
brain to spinal cord, efferent tract Voluntary movement of skeletal muscles
107
Vestibulospinal tract
brain to spinal cord, efferent tract Visual stimulus
108
Spinal Nerves Designation
C1-8, T1-12, L1-5, S1-5, Co1
109
Spinal Nerve Pairs
Cervical 8 Pairs, C1 - C8 Thoracic 12 Pairs, T1 -T12 Lumbar 5 Pairs, L1 - L5 Sacral 5 Pairs, S1 - S5 Coccygeal 1 Pair
110
Spinal nerve structure
Axon - ensheathed by endoneurinum formed by collagen fibers and elastin Fasicles - surrounded by perineurium formed by collagen fibers and elastin Entire nerve - ensheated by epineurium Formed by fibrous tissue
111
Branches of spinal nerves
Spinal nerves exit CNS into PNS, split into 3 major branches Anterior Ramus, Posterior ramus, Rami communicantes Rami are anterior division of spinal nerves
112
Nerve Plexuses
A long braided rope of nerves All anterior to spine Cervical Plexus, brachial plexus, Celiac solar plexus, Lumbar plexus, Sacral plexus, Coccygeal plexus
113
Cervical plexus
Anterior rami of C1 - C5 Serves head, neck, diaphragm Highlighted nerve: Phrenic nerves supply major muscle of respiration
114
Brachial plexus
Anterior rami of C5-C8 and T1 Serbes shoulders and upper limbs Divided into roots -\> trunks -\> divisions -\> cords -\> nerves risk takers don’t cautiously behave Erb’s palsy paralysis of arm as infants head and neck pulled toward side at same time as shoulders pass through birth canal Paralysis of arm at any age following trauma Carpal tunnel syndrome median nerve injury due to repetive motions of hand and wrist Highlighted nerve: Ulnar nerve largest unprotected nerve in human, supplies medial half of hand striking medial epicondyle of humerus = funny bone Highlighted nerve: Long thoracic nerve Supplies serratus anterior Damage cause winged scapula, arm cannot be abducted byond horizontal position
115
Lumbar plexus
Anterior rami of L1 - L4 Supplies anterolateral abdominal wall, external genitalia, lower limbs Highlighted nerve: Femoral and obturator nerves
116
Sacral plexus
Anterior rami of L4-L5, S1-S4 Sciatic nerve is largest in body
117
Coccygeal plexus
Anterior rami of S4-S5 Small area of skin in coccygeal region
118
Damage to the spinal cord
Transection of spinal cord means severing of ascending and descending tracts At base of skull - death by asphyxiation Upper cervical area - quadriplegia Between the cord enlargements - parplegia Less sensation, can’t sweat, less body hair, can’t cough
119
Tracts, Nerves, Ganglion, Nucleus, Plexus
Bundle of Axons Tracks (CNS): A series of axons grouped together in CNS Nerves (PNS): A bundle of axons and their sheaths that connects CNS to sensory receptors, muscles, and glands Group of cell bodies Nucleus (CNS): clusters of neurons Ganglion (PNS): collection of neuron/nerve cell bodies Plexus (PNS): extensive network of axons, sometimes neuron cell bodies

Comparative Vertebrate Anatomy (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions