module 5.1 Flashcards
The ability of the brain to change its anatomy over time, within limits is known as
plasticity
regression
connectivity
long term potentiation
plasticity
The human central nervous system
begins to form during the fetal stage
is unlike all other vertebrate central nervous systems in its developmental process
begins to form when the embryo is about two weeks old
begins to form when the embryo is about two months old
begins to form when the embryo is about two weeks old
Stem cells are important for which of the following developmental processes?
migration
proliferation
myelination
synaptogenisis
proliferation
As the neural tube sinks under the surface of the skin, the forward end enlarges and differentiates into the:
spine, midbrain, and forebrain
hindbrain, midbrain, and forebrain
hindbrain, midbrain
midbrain, forebrain
hindbrain, midbrain, and forebrain
Children of mothers who smoke cigarettes during pregnancy are at increased risk of
intellectual deficits
Korsakoff’s syndrome
Rett syndrome
Parkinson’s disease
intellectual deficits
Competition of neurons for postsynaptic sites results in survival of only the most sucessful axons. This general principle is called:
natural selection
evolution
apoptosis
neural Darwinism
neural Darwinism
Early in development the nervous system begins as a:
A tube surrounding a fluid filled cavity
spherical structure in the center of the embryo
diffuse system of cells scatered throughout the body
single layer of cells covering the heart and other internal organs
A tube surrounding a fluid filled cavity
Axons sort themselves over the surface of the target area
by following a gradient of chemicals
through apoptosis
through necrosis
based on their size
by following a gradient of chemicals
Apoptosis
is a programmed mechanism of cell death
promotes the survival and growth of the axon
promotes the survival and growth of dendrites
promotes teh activity of neurons
is a programmed mechanism of cell death
The final stage of neurodevelopment is called:
synaptogenisis
differentiation
migration
fusion
synaptogenisis
Myelination in the human brain:
is complete upon birth
is complete around the second birthday
is complete sometime shortly after adolescence
continues well into the adult years
continues well into the adult years
How much alcohol, if any, can a pregnant woman drink without worrying about the negative effects on her child?
The equivalent of two cocktails a day
The equivalent of one beer a day
Anything less than what causes her to act drunk
Unknown, and therefore abstention is recommended
Unknown, and therefore abstention is recommended
The mechanism of fetal alcohol syndrome probably relates to
over excited neurons
apoptosis
decreases apoptosis
necrosis
apoptosis
What happened when Weiss grafted an extra leg onto a salamander adjacent to one of the hindlegs
the new leg gradually took over for the old
the new leg withered and died
nerves from the old leg attached to the new in a random fashion
Branches of axons from the old leg attached to corresponding muscles in the new
Branches of axons from the old leg attached to corresponding muscles in the new
Why is it that all neurons in a health adult brain have made appropriate connections?
Chemical messages from our muscles tell our brain how many neurons to form and that number perfectly matches the connections required
if an axon does not make the appropriate connections by a certain age, it dies
we are born with all connections formed
connections form rapidly, but we learn to use whatever connections have formed
if an axon does not make the appropriate connections by a certain age, it dies
Alcohol suppresses the release of _________, the brain’s main excitatory transmitter.
5-HT
DA
GABA
glutamate
glutamate
Brain studies of blind people suggest that they have greater attention to touch and auditory stimulation because
cortical areas for touch and audition are thicker
their visual cortex is used for touch and verbal tasks
they have greater neural branching
they have greater neurotrophin release
their visual cortex is used for touch and verbal tasks
The most likely explanation for the excess proliferation of neurons in early development is that it
compensates for the connection errors
uses up excess stored fuel
increases learning capactiy when it is most needed
prevents apoptosis
compensates for the connection errors
Which of the following aspects of brain and neural functioning can be most clearly altered by experience?
velocity of action potentials
structure of dendrites and axons
chemical constituents of the ventricles
number of laminae in the cerebral cortex
structure of dendrites and axons
The fluid-filled cavity of the developing neural tube becomes the
forebrain
midbrain
spinal cord
ventricular system
ventricular system
Roger Sperry cut a newt’s optic nerve and rotated the eye. Axons form what used to be the dorsal part of the retina (now located on the ventral side) grew back to the target areas:
that ordinarily get input from the dorsal retina
that ordinarily get input from the ventral retina
that ordinarily get input from the center of the retina
equally and diffusely
that ordinarily get input from the dorsal retina
Children of mothers who use cocaine during pregnancy
have a slightly higher birth weight
are likely to develop Turner’s syndrome
have a slightly lower IQ
are born with severe abnormalities resembling cerebral palsy
have a slightly lower IQ
Developing neurons need _______ for survival
neurotrophins only
neurotropins and synaptic input
synaptic input only
apoptosis
neurotropins and synaptic input
Children of mothers who drink heavily during pregnancy are born with
fetal alcohol syndrome
Turner’s syndrome
Klinefelter’s syndrome
PKU
fetal alcohol syndrome
Which of the following would most likely interfere with migration of neurons during development?
altering chemical paths
damaging dendrites
loss of myelin
increased differentiation
altering chemical paths
What visual capabilities did Sperry’s newt have after Sperry cut the optic nerve and rotated the eye?
it regained normal vision
it saw the world upside down and backwards
it required experience to relearn how to see
it remained blind
it saw the world upside down and backwards
What is signaled by nerve growth factor (NGF)?
That a target cell has “accepted” an axon
which target cell a growing axon should connect with
that axons should elongate as the body grows bigger
the need for new neurons to form in the brain areas that are lacking in neurons
That a target cell has “accepted” an axon
Whether or not a transplanted immature neuron adopts the properties of neurons in the new location or retains at least some properties of neurons from where it was taken depends largely on how much the transplanted neuron has:
myelinated
proliferated
migrated
differentiated
differentiated
Keeping animals in a varied environment with stimulation increases the
branching of dendrites
speed of action potentials
density of Nodes of Ranvier along the axon
thickness of axons
branching of dendrites
Focal hand Dystonia, sometimes called “musician’s cramp” is caused by
extreme overlap of cortical representation of the fingers
deterioation of muscles in the hand
demyelination of neurons in the fingers
buildup of excess GABA in the temporal cortex
extreme overlap of cortical representation of the fingers
What is the process called when the primitive neuron begins to develop dendrites and an axon?
differentiation
migration
myelination
proliferation
differentiation
New neurons are known to develop in all of the following cases EXCEPT:
olfactory receptors
the human corpus callosum
the brain area responsible for birdsong
hippocampus of mammals
the human corpus callosum
Myelination is a process common to:
all vertebrate axons
all vertebrate dendrites
some vertebrate axons
some invertebrate axons
some vertebrate axons
After the migrating neuron reaches its destination, _______ begin to form.
dendrites
axons
nuclei
ganglions
dendrites
Which of the following, if any,, would be more damaging to an adult brain than to the brain of an infant or fetus?
Exposure to alcohol
Infections like German measles
Iodine deficiency in the diet
All of these are more damaging to an infant brain
All of these are more damaging to an infant brain
Proliferation occurs:
at the top of the spinal column
around the vesicles
around the ventricles
at the expanding edge of the brain
around the ventricles
Necrosis
is a programmed mechanism of cell death
is cl death caused by an injury or a toxic substance.
promotes the survival and growth of dendrites
promotes the activity of neurons
is cl death caused by an injury or a toxic substance.
After maturity, the apoptotic mechanisms become
hyperactive
extinct
dormant
very complex
dormant
Which of the following are selective as axons form synapses with target cells?
axons, but not target cells
target cells, but not axons
both axons and target cells
neither axons nor target cells
both axons and target cells
Research in people over age sixty who were randomly assigned to experience six months of aerobic exercise showed:
that they developed more axons
that they developed less tumors
that they developed greater thickness of the cortex
that they developed less thickness of the cortex
that they developed greater thickness of the cortex
Immunoglobulins and chemokines play an important role in neural:
migration
proliferation
synaptogenesis
apoptosis
migration
Which of the following is NOT a function of neurotrophins
Direct axonal growth during development
Increase axonal branching in mature neurons
Increase regrowth of axons after brain damage
Induce apoptosis of neurons
Induce apoptosis of neurons
What statement most accurately describes embryonic development of the nervous system in humans?
The majority of cells remain as primitive neurons until birth
All synapses that are formed are permanent
Neurons from before birth; synapses form after birth
Far more neurons are produced than will ultimately survive
Far more neurons are produced than will ultimately survive
What modern practice helps prevent inadequate production of thyroid hormones?
fluoride in drinking water
processed sugar
iodized salt
artificial sweeteners
iodized salt
What is the production of new neurons called
differentiation
migration
myelination
proliferation
proliferation
Brain cells that are neither neurons nor glia, but which are capable of dividing and then differentiating into neurons or glia, are called:
parallel fibers
intrinsic cells
stem cells
glomeruli
stem cells
________ steer new axonal branches and synapses in the right direction
Chemokines
Immunoglobulin
Glia
Neurotrophins
Neurotrophins
An iodine deficiency in the diet can lead to an inadequate production of thyroid hormones. What is the result if this occurs in an infant or develpoping fetus?
Down’s syndrome
mental retardation
Tourette’s syndrome
accelerated body growth
mental retardation
In humans, myelination first occurs in the:
spinal cord
hindbrain
midbrain
forebrain
spinal cord
Massive cell death in the brain during parental development is
indication of a genetic abnormality
an indication of restricted blood flow to the fetus
usually due to an autoimmune disorder
normal
normal
