WEEK 4 - GENETICS Flashcards
(120 cards)
1
Q
base pairs
A
adenosine and thymine
cytosine
guanine
code for different gene products
2
Q
dna structure
A
two strands
making up a double helix structure
3
Q
dna function
A
replicates and stores genetic material: blueprint
4
Q
dna base pairs
A
A-T
C-G
5
Q
rna structure
A
one strand: shorter
6
Q
rna function
A
brings to expression
ie, protein production
7
Q
rna base pairs
A
A-Uracil (different)
G-U
8
Q
number of human chromosomes
A
46
23 pairs
9
Q
down syndrome chromosome
A
21
10
Q
sex linked genes:
A
genes on sex chromosones, X and Y
all other genes are called autosomal genes
11
Q
sex limited genes
A
present in both sexes, but active mainly in one sex
ie, breast size
12
Q
duchenne disease
A
muscular dystrophy is inherited in an X-linked recessive pattern, meaning it primarily affects males and is passed down by carrier females.
13
Q
if a female has x linked recessive disorder what parent?
A
her father must have the disorder, need two XX to get the disorder
14
Q
gene expression depends on
A
location in the body
developmental phase
experience
availability of food
drug addiction
social isolation
15
Q
can epigenetic changes be inherited?
A
yes,
ex: person who was anorexic and had a overweight baby
16
Q
candidate gene approach
A
identifies specific genes linked to behaviour
17
Q
GWAS
A
examines all genes while comparing two groups
18
Q
neural tube defects
A
auenecephaly
spina bifida
19
Q
auenecephaly
A
Failure of the anterior neural tube opening to close
no brain dev can lead to death (before or right after birth)
20
Q
spina bifida
A
failure of the posterior neural tube opening to close
tissue comes out of spinal cord
21
Q
how to prevent neural tube defects
A
take folic acid
right away
22
Q
proliferation
A
production of new nervous cells
birth of new primitive cells in the ventricles
23
Q
migration
A
Primitive cells migrate to their destination
24
Q
differentiation
A
Primitive cells become neurons or glia cells
25
synaptogenesis
formation of synapses
26
myelination
glia starts producing insulating fatty sheaths (from caudal (back) to rostral (front )
27
dev of neuron stages
proliferation
migration
differentation
synaptognesisi
myelination
28
sperrys experiemnt on nerve connections
involved studying patients with a split brain (where the two hemispheres were disconnected) to show that each hemisphere has specialized functions, and they can work independently.
Testing if retinal axons will grow back?
29
sperrys findings
Retinol neurons were able to grow back to their original target
showed that neurons can follow chemical gradients
30
which glial cells support migration
radial glia cells
31
apoptosis
programmed mechanism for cell death
32
cell loss during CNS dev
The number of motor neurons peaks at 11 weeks after conception and then steadily drops
33
Which substances can prevent apoptosis
neurotrophins, for example
NGF - nerve growth factor
BDNF - brain-derived neurotrophic factor
34
why do neurons have a spontaneous firing rate
so they don't lose connections with other neurons
35
synaptogenesis
increase in synapses
36 weeeks - 2 years
36
synaptic pruning
4-6 years
Use it or lose it
37
what direction does myeleination go
back to fron
visual cortex is myelanted earlier than prefrontal
first in, last out
last in, first out
38
alzheimers disease example
tacticle and visual stimuli dev early are still in tact even though frontal functions (recent memories)
*maintain sensory functions
39
why does the brain need stimulation
You will start to hallucinate in total isolation
40
Effects of a stimulating environment
Jewelfish reared with others have more dendritic branches than when alone
41
How does musical training influence the brain
thicker inferior visual cortex and thicker inferior frontal gyrus (executive functioning)
positive effect on brain
42
writers cramp
Two fingers start to feel and move as one
Somatosensory reorganization
*The central problem in the brain
43
brain damage CVA (stroke)
hemorrage (blood vessels popped)
ischemia (obsutruction of blood vessel in brain)
transient ishemic attack (TIA) - transiet obstruction in brain
44
treatment after stroke right away
tPA: tissue plasminogen activator
reduce overstimulation:
blocking glutamate receptors
cannabinoids decrease glutamate release
cooling the brain, antixoidants, antibiotics (counteract infection)
albumin (against brain swelling)
treatments targeting the immune system
45
tPA: tissue plasminogen activator
breaking up blood clots
can make thigns worse so must be careful
46
diaschisis
Reduced activity in connected neurons
47
denervation supersensitivity
increased sensitivity in remaining synapses
48
Jody's video on plasticity
Removed half Brian
still finished my degree and function normally for the most part
49
phantom limb pain
Side effects of amputation
50
What causes phantom limb pain
Reorganization of the somatosensory cortex
51
memory
one of the higher cognitive functions
52
memory 3 things
related to the processing and storing of information
retaining information for shorter or longer periods of time
recognizing or actively recalling information
53
classical conditioning
conditioned stimulus to a conditioned response
learns association
54
instrumental conditioning
learning through reinforcement and punishment is presented in response to a specific behaviour
55
types of memory
hebb (1949)
short term memory
long term memory
56
2 types of long term memory
episodic memory
semantic memory
57
episodic memory
personal events
58
semantic memory
factual knowledge
59
2 types of short term memory
sensory memory (less can one second also known as iconic memory)
working memory (+- 4 items)
60
sensory memory partial reports experiment
type letter that saw
- WM theory suggests could recall 4
61
amnesia
memory loss
impairments not for all types of memory
62
procedural memory
"how to ride a bike"
63
types of amnesia
retrograde
anterograde
64
retrograde amnesia
loss of memory of events that took place before brain damage
65
anterograde amnesia
inability to form new memories after brain damage
66
what memory does retrograde affect
long term memory
"who was first love"
67
what type of memory does anterograde amnesia affect
short term "what did i eat today"
68
korsakoffs syndrome
caused by thiamine def (vitamin b1)
extreme alcoholic/anorexic
69
unique symptom of korsakoffs syndrome
confabulation
- patients give plausible answers" lying but patients are not aware
70
korsakoffs syndrome effects
apathy
confustion
memory loss
71
what does korsakoffs syndrome not affect
wm/STM
LTM/ episodic memory
72
alzheimers disease
common old
gradual increase in memory loss, confusion, depression, restlessness, insomnia and reduced appetite
73
what type of disorder is down syndrome often likely to develop in
early onset alzheimers
(gene associated
74
causes of alzheimers disease (AD)
different genes associated with late onset
AD: epigenetic changes
accumulation of amyloid-b early onset
AD: this protein
- damages axons and dendrites
- reduced synaptic input
- reduces plasticity
75
neuronal degeneration
damaged dendrites and axon cluster together in plaques
76
cascade hypothesis
large amounts of amyloid b cause changes in tau [proteins, ultimately to tau buildup and tangles
77
childhood amnesia
not a disorder
universal experience - do not remember much from first years of life
78
childhood amnesia hypothesis
learning language and complex reasoning abilities do not develop until the child is older
changes in the hippocampus and growth of new neurons
79
case H.M
underwent bilateral medial temporal lob suffering from epilepsy
treated his seizures but led to severe memory impairments
80
case H.M memory affects
epidosic memory (learn new things about personal life)
anterograde and retrograde mems
81
was semantic memory intact for H.M
yes he could learn new facts
82
delayed matching to sample tasks
subject sees an object and must later choose the object that matches
83
delayed nonmatching to sample tasks
subject sees an object and must later choose the object that is different from the sample
84
hippocampus and declarative memory test
delayed matching to sample tasks
delayed nonmatching to sample tasks
85
important region related to memory
hippocampus
86
hippocampal functions
recent mems with a lot of contextual detail are hippo dependant
navigation and spatial orientation
87
memories with less contexual detail are dependant on what brain region (recent memories)
cerebral cortex
88
tasks that hippocampus play a role in
radial maze
morris water maze
89
cells hippocampus
place cells: tat respond to a cetain location when a route is planned
time cells: coding for ordination in time
90
entorihinal cortex cells
grid cells: coding for a location in a hexagonal grid
91
Hippocampus =
Striatum =
memory you think about
memory you do without thinking
92
hippocampus learning speed
can learn in a single trial
93
hippocampus type of behviour
flexible responses
94
hippocampus based on what type of feedback
sometimes connects info over a delay
95
hippocampus explicit or implicit
explicit
96
hippocampus what happens after damage
impaired declarative memory
esp episodic memory
97
striatum speed of learning
learns gradually over many trials
98
striatum type of behaviour
habits
99
striatum based on what type of feedback
generally requires prompt feedback
100
striatum explicit or implici
implicit
101
striatum impacts after damage
impaired learning of skills and habits
102
structure basal ganglia
globus pallidus + subthalamaic nucleus + substanstia nugra + striatum
103
striatum brain strcuture
caudate nucleus and putamen
104
probalasitic learning
weather prediction task
participant predicit will it rain or shine
105
weather prediction task results
with more trials you will get better, even if u are unable todesrcibe your strategy
gradual PROBABLSIITC LEARNING DEPENDS ON THE BASAL GANGLIA
106
what brain structure to parkinson patients have
damage in striatum
- deterioration in substanstia nigra
107
weather prediction task parkinsons pateints
first get better on this task (hippocampal learning) while later (stratal) habit learning is impaired
108
hebbian synapse
a synapse that increases in effectiveness bc of simultaneous activity in the presynaptic and post synaptic neurons
such synapses may be critical for many kinds of associative learning
109
learning in invertebrates
has large neurons
fundamental principles of learning similar in mammals
110
habituation
decrease in response to a stimulus presented repeatedly
- test the invertebrates
111
sensitisation
increase in response to a mild stimulus as a result to previous exposure to more intense stimuli
112
2 processes happen in aplesia c snail
habitutation
sensitization
113
long term potentiation (ltp)
occurs when one of more axons bombard a dendrite with stimulation and leaves the synapse "potentiated" for a period of time making the neuron more responsive
114
specificity
only synapses onto a cell that have been highly active become strengthened
115
cooperativity
simultaneous stimulaiton via two or more axons produce LTP much more strongly than does repeated stimulation by a single axon
116
associativity
pairing a weak input with a strong input enhances later responses to a weak input
117
what causes EPSP
spatial summation (stimulation from 2 different axons at same time)
118
long term depression
a prolonged reduction in responsitivity at a synapse, that occurs when certain axons have been less active than others
compensatory process: as one synapse strengthens, another weakens
119
LTP in the hippocampus
1. repeated glutamate excitation of AMPA receptors depolarize membrane
2. depol displaces mag molecules that blocked NMDA receptors
3. glutamate is then able to excite the NMDA receptors, opening a channel for calcium ions to enter the neuron
4. entry of calcium through the NMDA channel triggers furhter changes
5. activiation of a protein set a series of events in motion
6. more AMPA rec are built and dendritic branching is increased
7. these changed potentiate the dendrites future responsivness to incoming glutamate
120
LTP VS LTD
LTP is when brain cells get better at talking to each other because they keep getting used.
LTD is when brain cells get worse at talking to each other because they aren’t used much
