Midterm Three Flashcards
(100 cards)
1
Q
what are the hallmarks of Lissencephaly?
A
- white/grey matter blends together
- enlarged ventricles
- smooth cortex
- patients normally die prenatally
2
Q
the diencephalon is ______ the cortex
A
beneath
3
Q
forebrain diverges into
A
telencephalon and diencephalon
4
Q
telencephalon diverges into
A
cerebrum
5
Q
diencephalon diverges into
A
diencephalon (thalamus, hypothalamus, epithalamus)
6
Q
midbrain diverges into
A
mesencephalon
7
Q
mesencephalon diverges into
A
midbrain (in brainstem)
8
Q
hindbrain diverges into
A
metencephalon, myelencephalon
9
Q
metencephalon diverges into
A
pons, cerebellum
10
Q
myelencephalon diverges into
A
medulla
11
Q
caudal neural tube diverges into
A
spinal cord then central canal
12
Q
embryo development pathway
A
zygote -> blastula -> gastrulation (blastocoel) -> segmentation ->organogenesis
13
Q
what is a stem cell?
A
self-renewing, differentiates into multiple cell types (pluripotent)
14
Q
_____ stem cells only produce neurons, astrocytes, and oligodendrocytes
A
neural
15
Q
neural stem cells do NOT produce_______
A
microglia
16
Q
symmetric division
A
two cells of the same type
17
Q
asymmetric division
A
two cells of different types
18
Q
how do cells know to differentiate?
A
from external environmental signalling
19
Q
cell division is either symmetric or asymmetric depending on what
A
where the mitotic spindle aligns
20
Q
the nervous system forms from what
A
the ectoderm
21
Q
melanocytes and the adrenal medulla form from
A
the ectoderm
22
Q
the neural crest gives rise to
A
PNS neurons
23
Q
the LAST part of the neural tube to close is the
A
caudal most piece
24
Q
FAILURE of the spinal cord to close results in
A
spina bifida
25
what is a key neural progenitor
radial glial cells (RGC's)
26
stages of cell proliferation
proliferative stage, neurogenic stage
27
proliferative stage
lateral expansion of neural tube
28
neurogenic stage
radial (outward) growth and specialization of neural tube
29
the cortex develops ___-____
inside-out
30
the oldest neurons of the cortex are _____
deepest
31
layer one
no neurons, only dendrites
32
layer two
youngest stage neurons
33
layer six
oldest stage neurons. white matter below and thalamic output
34
neural migration occurs along the
RGC
35
layer 4
thalamic input
36
reelin
a mutation resulting in cell death
37
_____ brains are much thicker and have more cells than ______ brains
primate, rodent
38
neural stem cells keep _____-ing
renew
39
basal radial glial cells (bRGCs)
proposed to determine degree of cortical folding
40
IP
intermediate progenitor. differentiates complex cortex
41
inhibitory interneurons
migrate into developing cortex from progenitor zones into ventricles and medial regions of the developing brain
42
zika virus
mosquito-borne virus. causes microcephaly in newborns
- cell cycle arrest
- apoptosis of post-mitotic neurons
43
induced pluripotent stem cells
a method to reprogram human somatic cells into a stem cell-like state
44
how long does it take for the neural tube to close
28 days
45
anencephaly
defect in closure of anterior neural tube
46
spina bifida/meningomylocely
defect in closure of posterior neural tube
47
the mammalian cortex has __ layers
6
48
to form the cortex, neuronal migration occurs from the birthplace near the ______ zone up to the ______ zone
ventricular, marginal
49
lissencephaly occurs from what
cell migration defects in cortical development
50
LIS1 protein affects __________ which travels retrograde
dynein
51
x-linked double cortin
results in double cortex. affects more males
52
heterotopia
'out of place'
53
microtubules play a part in
cell division, migration, and neurite growth
54
nearly all cortical malforms result in
seizure disorders
55
how many unprovoked seizures (separated by 24 hours) must one have to be diagnosed with the disorder
2+
56
generalized seizures
affect both sides of the brain
57
focal seizures
affect 1 area in the brain aka "partial" seizures
58
rare instances of seizures can occur from
channelopathies or ion channel imbalance
59
meds targetting ion channels target what in particular
GABA-A receptors
60
focal cortical dysplasia
clumps of abnormal cells in cortex
61
hemimegaencephaly
rare genetic condition in which parts of brain is abnormally larger than the rest
62
what is ASD
- neurodevelopmental disorder
- deficits in communication/social interactions
- restricted, repetitive behavior/ interests/ activities
63
why is there now a higher frequency of diagnoses of ASD
more awareness of Sx
64
ASD is comorbid with
anxiety, OCD, ID, ADHD, aggression, sleep disorders
65
Aspergers
mild, very intelligent, discuss favorite topics constantly
66
pervasive developmental disorder (PDD)
autism that's more severe than Asperger's but not as severe as ASD
67
autistic disorder
same Sx as PDD but more severe
68
childhood disintegrative disorder
rarest and most severe. children develop normally but then lose all social, cognitive, language skills between ages 2-4. also develop seizures
69
ID
intellectual disorder. limitations in intellect before age 22. IQ of 70-75
70
syndromic definition and examples
intellect deficits and/or ASD that's associated with medical and behavioral signs and Sx. ex: Fragile X, Downs
71
non-syndromic
intellectual deficits and/or ASD that appear without other abnormalities
72
down syndrome
extra chromosome 21. increased risk for other health conditions like ASD, endocrine disorders etc
73
CNV
portions of a chromosome that have been deleted or duplicated
74
syndromic forms of ID/ASD are traced to
single gene variants or CNV
75
phelan-mcdermid syndrome
partial deletion in Cr 22q13 or a mutation in SHANK3 gene
76
ASD is ___% heritable and ___% environmental
52, 48
77
what is the most common hereditary cause of ID/ASD
fragile X syndrome
78
Fragile X is caused by what mutation
FMR1 mutation in the FMRP protein
79
what is the criteria for designating a compound as a "neurotransmitter"
1. present in nerve terminals
2. released upon depolarization
3. acts on a target cell via ligand activations
80
dopamine is a type of _______
catecholamine
81
hallmarks of catecholamine synthesis
1. tyrosine hydroxylase is rate limiting step (creates 'catachol')
2. synthesis occurs in cytoplasm of nerve terminals
3. loaded into syn vesicles by VMAT (vesicular monamine transporter)
82
DA neurons in the _____ _____ project to the striatum and elsewhere
substantia nigra
83
N. Accumbens at cortex get DA from
VTA
84
all noradrenergic transmission in brain comes from
locus coeruleus
85
NE in CNS
sleep, arousal, emotional state
86
NE in PNS
autonomic activity
87
epinephrine
NT but produced in adrenal glands and can be considered a hormone
88
all synaptic vesicles contain
ATP
89
___________ is released from neurons and glia but NOT from vesicles
adenosine.
90
purinergic receptors respond mainly to
ATP
91
how are peptide neurotransmitters synthesized
DNA -> mRNA -> protein
92
nitric oxide is produced by
NO synthase
93
unconventional NTs/ modulators can serve as
retrograde signals
94
two most predominant second messengers
cAMP, Ca2+
95
cAMP is made from
adenylyl cyclase
96
to stop signaling, cAMP is converted to AMP by which enzyme?
phosphodiesterase
97
what is the main target of cAMP
PKA
98
Gi receptors ________ protein phosphorylation
decrease
99
Gs receptors __________ protein phospphorylation
increase
100
