Exam 3 Flashcards
(164 cards)
1
Q
Tract
A
Axons (white matter) travelling in CNS
2
Q
Nerve
A
axons in PNS
3
Q
Ganglion
A
Cell Bodies in PNS
4
Q
Glia
A
Outnumber neurons 10:1
Sattelite and Schwann Cells
5
Q
Amount of Afferent vs. Efferent neurons
A
5x more afferent than efferent
6
Q
Cervical Plexus
A
Head and neck nerves
7
Q
Brachial Plexus
A
Upper Extremities nerves
8
Q
Lumbosacral plexus
A
lower extremities nerves
9
Q
Astrocytes
A
Surround capillaries and induce blood brain barrier, surround synapses, NT uptake
10
Q
Microglia
A
secrete inflammatory chemicals, perform phagocytosis
11
Q
Ependymal cells
A
line ventricular surface, secrete cerebrospinal fluid
12
Q
Oligodendrocytes
A
from CNS myelin
13
Q
Same time
A
temperal summation
14
Q
different time
A
spatial summation
15
Q
Localization
A
smaller field + more overlap = better localization
16
Q
Lateral inhibition
A
Sharpens contrasts
Happens in grey matter
17
Q
Presynaptic inhibition
A
GABA blocks postsynaptic AP’s
18
Q
Dorsal Column
A
Very Direct pathway, transmits info about proprioception, 2 pt discrimination, pressure
19
Q
Fasciculus Gracilis vs. Cuneatus
A
Gracilis = Lower
Cuneatus = upper (u=upper)
Both contain first order neurons, ascend same side of body, synapse and cross in medulla
20
Q
Medial lemniscus
A
2nd order neurons, start at medulla and goes to thalamus to synapse
21
Q
Internal capsule
A
3rd order neurons, go from thalamus and ascend to S1 for processing
22
Q
Spinothalamic, Spinaltectal, Spinoreticular tracts
A
pain, eye movements, spinal cord and stuff
23
Q
Anterolateral system
A
pain, temperature, crude touch
Very Divergent! Cannot tell were stuff is coming from
24
Q
Homonculus
A
Brain map, different body parts mapped to different brain parts
25
Pain
Receptors are unmyelinated free nerve endings
| Pain afferents produce substance P
26
Analgesic
stimulate grey matter regions to produce pain relief
27
Opiate drugs
Block substance P release, used as painkillers
28
Vestibular system
Utricle, Cochlear duct, Ampulla, vestibulocochlear nerve, semicircular canals, cupula
29
Static equilibrium sensed by __
Hair cells of utricle
| Otolith moves by gravity
30
Linear Acceleration sensed by ___
```
Horizontal = utricle
Vertical = Saccule
```
31
Angular acceleration sensed by
Semicircular canals
32
Path of sensory transduction to brain
Sensory neurons, vestibulocochlear nerve, cerebellum, vestibular nuclei of medulla, oculomotor center
33
Reflex movement
Rapid, involuntary, fixed, specific stimuli
34
Rhythmic movement
Initiation + Termination voluntary, middle is not - Walking, chewing, running
35
Voluntary movement
Improves with practice - entirely from CNS - Dancing, pitching, writing
36
Higher centers of control
decision making
Supplementary motor area
Frontal cortex
37
Middle center of control
Coordinator
Convert commands
Thalamus, basal ganglia, brainstem, cerebellum
38
Local center of control
Operators
Specify regional movement
Brainstem, spinal cord
39
Extrafusal muscle
Skeletal muscle from exam 2,
| Alpha motor neurons
40
Intrafusal muscles
gamma motor neurons, sensory afferents
| Two ends of muscles stretch to contract the middle
41
Muscle Spindles where?
Found in intrafusal muscle
42
Golgi tendon organs
On Tendons
Monitor tension in tendon
Activation causes inhibition of contracting muscle, activation of antagonistic muscle
43
Gamma motor neuron
Stretches spindles as muscle contracts
| "Biased" muscle allows stretch to be sensed at all muscle lengths
44
Knee Jerk
Monosynaptic
| Inhibits antagonist muscles so reflex is mad fast
45
Step on tack reflex
```
Anterolateral tract (pain)
Pull back one foot, extend other leg
```
46
Spinal cord is hardwired for___
For rhythmic stereotyped movements
47
Dorsolateral tracts are _____ tracts
motor
| Include lateral corticospinal and rubrospinal
48
Lateral corticospinal tract
Dorsolateral
Fine movements of fingers
Only primates have this
Involved in STEREOGNOSIS
49
Rubrospinal tract
Dorsolateral
| Influences motor neurons innervating more distal muscles
50
Ventromedial tract function
Control axial and proximal muscles
51
Superior colliculus
visual and audio input
52
Reticular formation
Muscle Tone control
Via reticulospinal tract
Contracts lower extremity EXTENSORS and upper extremity FLEXORS to fight gravity
POSTURE
53
Spasticity
Damage to reticular formation
54
Basal ganglia
actually nuclei
Initiation of movement
Damage = Parkinson's disease
55
Symptoms of parkinson's
bradykinesia (slow movement)
resting tremor
Cogwheel rigidity = high tone
Loss of dopaminergic neurons
56
Other disorders from damage to basal ganglia
Huntington's - lots of involuntary movement
| Ballismus - arm acts like a whip
57
Cerebellum
Initiation, timing, coordination of movements
| Motor learning and planning
58
Cerebellum damage disorders
Ataxia, incoordination, tremor upon movement (tremor when reaching for that magazine)
59
Primary motor cortex
Middle level of movement control
Individual postures and movements
Converts commands
60
Primitive reflexes
Present in infants, go away with myelination as frontal lobe develops
61
Rooting reflex
touch baby's cheek, baby orients to the touch
62
Grasp reflex
Baby grasps anything placed into hand
63
Startle reflex
Baby puts arms out when startled/falling
64
Tonic neck reflex
Turn baby's face to one side, arm and leg on facing side extends, opposite side will flex
65
Highest level of motor control
Premotor cortex = complex strategies
Supplementary motor cortex = planning
Posterior parietal cortex = visual info and targeted movements
66
Illusions
Mind interprets based on context given
67
Signal processing
increased contrast, create/add info, begins in retina
68
Parallel processing
Processing multiple things at once
69
Optic nerves made of___
retinal ganglion axon cells
70
Receptive field
Position in space where light stimulus can affect cell
71
Center of visual field falls on____
Fovea
72
T/F: Receptive field for specific visual receptor is always in the same location in the visual field
True
73
Hierarchy of visual pathway
```
Receptors
Bipolar Cells
Retinal ganglion cells
LGN of thalamus
V1- primary visual cortex
Association visual cortex
```
74
Temporal/Lateral retina
Do not cross
| Gets info from offsite side's visual field
75
Nasal/Medial Retina
Crosses at optic chiasm
| Gets info from that side of visual field
76
Bipolar cells transmission path and method
Transmit with graded potentials to retinal ganglion cells
77
Retinal ganglion cells Transmission path and method
transmit with action potentials to LGN of Thalamus
78
Amacrine and Horizontal cells do _____
Lateral inhibition: To increase contrast between light and dark
79
Lateral inhibition first occurs in this part of the visual pathway
retina
80
Visual Transduction mechanism with channels
Rods and cones leaky to Na+ and Ca2+. Light photon will close cation channels and cause hyperpolarization, so NT release stops. NT = glutamate
81
"On" pathway bipolar cells
Have inhibitory glu RECEPTORS
Inhibited in the dark
Light stops release of glu, "on" pathway is no longer inhibited= lit
82
"Off" pathway
Have excitatory glutamate RECEPTORS
glu depolarizes
Off pathway excited in dark since glu released in dark and not in light
83
Retinal ganglion cells
AP's first possible here
| Need contrast in receptive field for response
84
On-center RGC
Light center, dark surrounding
85
Off-center RGC
Dark center, dark surrounding
86
Lateral Geniculate Nucleus
M cells - rods = movement
P-blob = color = cones
P-Interblob = form and depth = cones
87
V1 Primary Visual Cortex
Info about Form and Orientation of stimulus is added
88
Preferred orientations
Best = bar of light oriented at precise angle
Simple cortical cells require DISCONTINUOUS EDGE on that bar of light
Complex cortical cells require movement in a preferred direction and speed
89
Association visual cortex
Information from V1 sent to 30 visual agres
Face recognition
V4: Color processing - not just cones that sense color
90
Brain lateralization
Speech and language in left hemisphere
| Creativity in right hemisphere
91
Broca's vs. Wernicke's Area
```
Broca's = Producing Speech + written language - anterior
Wernicke's = Comprehending Speech and written language - posterior
```
92
CVA
Cerebrovascular Accident = Stroke
93
Blood Supply to the brain
Anterior, middle, and posterior cerebral arteries
94
Hemi-neglect
With right hemisphere damage - patients neglect left side
95
Left hemiplegia
Broca's aphasia - can still say a few meaningful words
| Wernicke's aphasia - says a bunch of nonsense
96
Lateralized emotions
Left hemiplegics = Blissful ignorance
| Right hemiplegics - hyperemotionalism
97
Autonomic nervous system
Involuntary, non-skeletal muscle
98
Autonomic neurons are different from somatic neurons because
They have a ganglion, so they have preganglionic neurons and postganglionic neurons
99
Sympathetic Chain Ganglia
Directly parallel to spinal cord
| Goes to heart and other organs
100
Sympathetic Collateral Ganglia
Found in abdominal cavity, only on ventral surface
101
Sympathetic preganglionic neurons originate in which spinal vertebrae
T1-L2
102
Adrenal Medulla
Specialized postganglionic cells which form endocrine gland
103
Chromaffin Cells
Secrete Epinephrine and norepinephrine
104
Parasympathetic Preganglionic bodies originate from
Several cranial nerves (3, 7, 9, 10)
| Also sacral region of spinal cord
105
Fight or flight response
Epi or NorEpi
Increase HR, Sweating, Respiiration
Constrict GI vessels, Dilate skeletal muscle vessels
106
Parasympathetic rest/digest response
Increased GI activity, dilate GI vessels, airway constriction, decrease resp. rate
107
Cholinergic neuron
Every somatic nervous system neuron and all PREGANGLIONIC cells and Postganglionic neurons in the Parasympathetic NS
Releases ACh
108
Adrenergic Neuron
Releases Epi/NorEpi
| Postganglionic neurons of sympathetic NS and Adrenal Chromaffin cells
109
ACh Receptors, 2 categories
Nicotinic - Postganglionic neurons of both divisions
Muscarinic - Target organs of Parasympathetic ONLY
If it says sympathetic ONLY, it means NICOTINIC!
110
What defines the response of adrenergic signalling?
Receptors define the response, receptors are specific!
111
Neurohormones
Secreted from neurons into the bloodstream
| Ex. adrenal medulla with Epi/norEpi
112
Processes under hormonal control
```
Fuel metabolism
Reproduction
Behavior
Vascular function
Cell Growth
Cell Differentiation
```
113
Preprohormones
AA sequences that need to be cleaved to be activated
| Cleave --> Prohormone --> Cleave --> Hormone
114
Steroid Hormone
From Cholesterol Backbone
| Testosterone/Estradiol
115
Peptide
Protein complexes
Insulin, PTH
Water soluble
116
Amine
From amino acid (smaller)
| Thyroid Hormones, catecholamines (epi, dopamine), melatonin
117
Regulation of receptors
Upregulation - More receptors, increase sensitivity
| Downregulation - Fewer receptors, decrease sensitivity
118
Nonsteroid hormone mechanism of action
Cannot pass membrane
| Binds to receptor, second messenger --> Amplification
119
Glucagon/Epinephrine - cAMP Pathway
Hormone binds GPCR, Ga has three forms. Pathway depends on the form
120
Galpha S
Stimulatory, cAMP production pathway, Adenylyl cyclase makes cAMP and activates PKA
BETA-ADRENERGIC
121
Galpha I
Inhibitory, Phosphodiesterase
Stop cAMP production
ALPHA-2 Adrenergic
122
Galpha Q
Q=Cleave, PLC cleaves PIP2 to IP3 and DAG... IP3 releases Ca2+, activate PKC
123
Muscarinic receptor pathway
Similar to Ga I, inhibitory, but the receptor binds ACh instead.
124
Receptor Tyrosine Kinases
Dimers cross phosphorylate
Associated with Growth
Cancer drugs will target these
125
Hormone secretion causes
```
Changes in:
Plasma [ion]
Plasma [organic nutrient]
NT Activation
Circadian rhythms
Tropic hormones
```
126
Regulation can be simple or complex
Simple: gland regulates its own hormone release
Complex: everything else
127
Permissiveness
Hormones modulating effect of other hormones
128
Pituitary gland
Anterior: epithelial tissue, endocrine gland
Posterior: Nervous tissue, neuroendocrine
129
Hypothalamus
Synthesizes hormones secreted by posterior pituitary, connected directly by hypophysial tract
Has 3 nuclei
130
Paraventricular Nuclei
PVN - releases ADH and oxytocin
131
Supraoptic Nuclei
Releases ADH and Oxytocin
132
Tuberal Nuclei of hypothalamus
Produces releasing hormones and release inhibiting hormones
133
Hormones of posterior pituitary
ADH and Oxytocin
134
Hypothalamus control of pituitary gland
Hypothalamus releases releasing hormones which interact with anterior pituitary
135
Anterior pituitary releases ___
Tropic hormones which act on endocrine tissue
136
Endocrine tissues secrete___
Effector hormones which effect non-endocrine tissues
137
FLAT PiG
FSH, LH, ACTH, TSH, Prolactin, Growth Hormone
138
Negative feedback in endocrine system
Ultra short loop: Releasing hormone on hypothalamus
Short loop: Tropic hormone on hypothalamus
Long loop: Effector hormone on hypothalamus and anterior pituitary
139
Positive feedback in endocrine system
Prolactin regulating milk production - oxytocin regulates milk release
More sucking = more milk release
140
Growth hormone Stimuli for release
```
Low Plasma [glucose]
Raised plasma [arginine]
Exercise
Sleep
Fasting
Stress
```
141
Effector functions of growth hormone
Lipolysis
| Raise plasma [glucose]
142
Tropic functions (somatomedins) of GH
Growth
AA uptake
Protein synthesis
Cell Growth
143
Regulation of growth hormone
```
Negative feedback, when Plasma [arginine] goes down
Circadian rhythm (reduced GH during day)
Fight or flight inhibits GH
```
144
Disorders involving growth hormone
```
Hyposecretion = Dwarfism
Hypersecretion = Gigantism or Acromegaly
```
145
Levels of negative feedback for growth hormone
Short loop and long loop
146
Follicular cells of thyroid
Release thyroid hormone
| Surround the follicles in thyroid
147
Apical side Basal Side of Follicular cells
Basal faces blood
| Apical faces Lumen
148
Process of T3 and T4 production
Iodine comes in symported with Na
Enzymes add I to tyrosine to make T3 and T4 in follicle
Thyroglobulin is taken back to cell in vesicles
Free T3 and T4 enter blood
149
TSH (Thyroid stimulating hormone)
Activates all steps of thyroid hormone synthesis
150
Cellular effects of thyroid hormone
Transcription of Na/K ATPase - increase O2 consumption
| Increase protein synthesis, glycogen breakdown, gluconeogenesis, FA oxidation
151
Systemic Thyroid hormone effects
Increase BMR + heat production
Synthesize adrenergic receptors
Regulator of tissue growth
152
Regulation of thyroid hormones
Inhibition = T4 levels inhibit TRH and TSH
Stimulation = Reduced T4 (increase TSH)
Cold Temperatures = Increase TRH)
153
Hypothyroidism
```
Cretinism = short disproportional body
Myxedema = Low BMR, dermal edema, lethargy, mental sluggishness
```
154
Causes of hypothyroidism
Problem with:
Hypothalamus = tertiary
pituitary = secondary
thyroid = primary hypothyroidism
155
Goiter
Abnormal enlargement of thyroid gland
| Cause: Iodine deficiency
156
Graves Disease
Autoimmune disorder - production of antibodies that function like TSH
Goiter
Increased BMR, bulging eyes, weight loss
157
Tracts that control posture
Anterior Corticospinal tract
| Reticulospinal Tract
158
High pitched sound activates sounds closer to___
oval window
159
Cell bodies for parasympathetic preganglionic neurons are where?
In the nucleus for the Vagus cranial nerve (X)
160
Autonomic nervous system controlled by
Hypothalamus - body temp and water balance
161
Atropine blocks ____
Salivation
162
Endocrine glands are they ductless?
Yes they are ductless
163
What kinds of hormones go through the hypophyseal portal?
Releasing hormones like TRH
164
Cortisol effect
Breakdown of protein - loss of gainz
