Exam 2 Flashcards
our environment influences gene expression
epigenetics
the environment can directly impact genetics
epigenetics
Michael Meaney at McGill University showed what in his research on maternal behavior?
offspring born to high-licking maternal rats exhibit less anxiety in the elevated plus maze compared with offspring from low-licking maternal rats
key takeaway from Michael Meaney’s study
manipulating the environment led to changes in gene expression
early differentiation
gastrulation
occurs between days 13-19 as the developing embryo reorganizes to form 3 germ layers
gastrulation
the three germ layers
ectoderm, mesoderm, endoderm
forms the skin and nervous system
ectoderm
forms the bones of the skeleton and muscle
mesoderm
forms the digestive tract and organs
endoderm
develops into the brain and spinal cord
neural tube
how is the neural tube formed
the ends of the neural plate fold inward
what does the neural tube do
allows for the CNS to develop and MOST of the PNS
what helps guide cells to their appropriate target locations
radial glia
radial glia are present when?
in cell migration
this type of disease is characterized by severe losses of memory and cognition
alzheimer’s disease
the two hallmarks of alzheimer’s
amyloid plagues and tau tangles
how is the hippocampus affected by alzheimer’s
there is a noticeable shrinkage of this area that leads to losses in memory and learning
clump up between cells and impair information transfer
amyloid plaques
tangle within the neuron and impair communication and axonal structure
tau tangles
process whereby environmental energy is converted into a neural signal that the brain is able to make sense of
sensory transduction
how the environment is converted to a form our brain can understand
sensory transduction
what holds the eye in place
extraocular muscles and the optic nerve
the optic nerve is what cranial nerve
cranial nerve ll
where light is able to enter the eye
pupil
has the ability to constrict or dialte to accommodate light
iris
located behind the pupil
lens
helps to focus light on the retina
lens
tissue layer containing photoreceptors and visual cells
retina
the transparent covering over the pupil and iris
cornea
provides more focusing power than the lens
cornea
what is the internal cavity of the eye filled with?
vitreous humor
space between the cornea and the lens is filled with what
aqueous humor
the axons of these cells make up the optic nerve
ganglion cells
carries visual information from the retina at the back of the eye to the brain
optic nerve
where is the optic nerve located
retina
the optic nerve exits where
the optic disc
the optic disc is also known as
the blind spot
the outermost cell layer of the retina
photoreceptors
the middle cell layer of the retina
bipolar cells
the inner most cell layer of the retina
ganglion cells
the only cells that are able to fire action potentials in the eye
ganglion cells
the photoreceptor cells are made up of what
rods and cones
rods detect what forms of light
black & white
cones detect what forms of light
color
where are rods located
periphery
where are cones located
fovea, macula
light-sensitive cells in the retina
photoreceptors
young-helmhltz trichromatic theory of color vision says what about the cones in the retina
medium, short, and long wavelengths of light are going to be received by cones, which will aid in our perception of color
11-cis-retinal + light = > all-trans-retinal + energy
The chemical reaction that occurs when light is absorbed by our rods
a steady inward flow of sodium ions into the retina’s rod outer segments that occurs in the dark
dark current
the dark current is usually at what charge
-40mV
the dark current
In the dark cGMP levels are high and keep cGMP-gated sodium channels open allowing a steady inward current keeping the cell in a depolarized state
how does the rod hyperpolarize in response to light
leads to reduced cGMP levels and closure of cGMP-gated sodium channels. Stopping the influx of Na+ ions effectively switches off the dark current. Reducing this dark current causes the photoreceptor to hyperpolarise, which reduces glutamate release
the optic tract and the optic nerve are the same
no
the bundle of nerve fibers connecting the retina of the eye directly to the brain
optic nerve
optic tract
the continuation of the optic nerve within the brain itself, occurring after the optic chiasm where some nerve fibers from each eye cross over, allowing for this to carry visual information from both eyes to the brain’s visual processing center
post-crossing part of the visual pathway
optic tract
pre-crossing part of the visual pathway
optic nerve
superior colliculus allows us to do what
localize what we see
the primary function of the superior colliculus does what
involvement in eye movements, head/visual orientation
the “what” pathway in the visual stream
ventral stream
the ventral stream allows us to do what
identify objects
the final destination of the ventral stream
inferior temporal cortex
the “where” pathway of the visual stream
dorsal stream
the dorsal stream allows us to do what
know information about the location of objects
the dorsal stream allows us to know the location of objects as well as
integration of vision with action
the final destination of the dorsal stream
posterior parietal cortex
the bones of the middle ear
malleus, incus, and stapes
the inferior colliculus allows us to do what?
localize sound and detect where sound is heard (L or R)
where does the “what” auditory pathway end in the brain?
prefrontal cortex
where does the “where” auditory pathway end in the brain?
posterior parietal cortex
the “where” auditory pathway allows us to do what
localize sound. orientation to the stimulus
the “what” auditory pathway allows us to do what
identify sound. can state what the sound is
the five basic tastes
salty, sweet, bitter, sour, umami
the two structures that are important for our emotional and hedonic responses to food
hypothalamus and amygdala
bipolar cells that detect and transmit odor information from the nasal cavity to the brain
olfactory receptor neurons
What sensory systems go through the thalamus first prior to going to their respective
cortices?
All sensory systems except for olfaction (smell)
What is the corticospinal tract
fibers going from motor cortex to the spinal cord
fibers in the corticospinal tract that go contralaterally aid in what
moving the distal limbs and digits
the contralateral fibers in the corticospinal tract are a part of what tract
lateral corticospinal tract
fibers in the corticospinal tract that remain ipsilateral aid in what
controlling muscles of the core or the midline of the body
the ipsilateral fibers in the corticospinal tract are a part of what tract
anterior or ventral corticospinal tract
2 major tracts of the corticospinal tract
lateral and anterior/ventral
the synapse formed between a motor neuron’s axon terminal and the motor end plate
neuromuscular junction
the reason as to why muscles contract
the neuromuscular junction
what neurotransmitter is present at the neuromuscular junction
acetylcholine
muscle spindles do what?
muscle spindles detect changes in muscle length (stretch),
golgi tendon organs do what?
Golgi tendon organs detect muscle tension and initiates a compensatory action when a muscle contracts excessively
antagonistic muscles do what
produce actions that are opposite of one another
when flexing the arm what happens
biceps contract
when extending the arm what happens
triceps contract
majority of neurons can be found where
the cerebellum
the cerebellum helps control what
movement coordination, balance, and muscle tone
a part of the cerebellum that controls muscle tone
vermis
a part of the cerebellum that helps with balance and posture
flocculonodular lobe
a part of the cerebellum that helps with motor and non-motor area communication
lateral cerebellar hemispheres
a part of the cerebellum that communications with additional brain regions
cerebellar peduncles
Huntington’s disease involves an abundance of repeats of what amino acid?
Huntingtin gene
What area of the brain deteriorates in Parkinson’s disease
substantia nigra
Broca’s area deals with
speech production (motor cortex)
Wernicke’s area deals with
speech perception and comprehension (learning & memory)
the visual system is connected to what thalamic nuclei
LGN
the auditory system is connected to what thalamic nuclei
MGN
the somatosensory system is connected to what thalamic nuclei
VPL
the central taste pathways is connected to what thalamic nuclei
VPM
the motor system is connected to what thalamic nuclei
VA/VL
Primarily involved in motor function, receiving input from the cerebellum and basal ganglia and sending it to the motor cortex.
VA/VL
Also part of the somatosensory system, but specifically receives facial sensory information specifically taste
VPM
Part of the somatosensory system, primarily relaying information about pain, temperature, and crude touch from the body to the cortex
VPL
Responsible for the auditory system, receiving sound information and sending it to the primary auditory cortex
MGN
Associated with the visual system, receiving information directly from the retina and relaying it to the primary visual cortex
LGN
helps store glucose as glycogen
insulin
assists in moving glucose from the blood supply into body cells
insulin
produced by fatty tissue
leptin
a critical hunger regulatory signal conveying metabolic information from the body to the hypothalamus
leptin
low levels of this hormone and insulin stimulate the release of NPY and AgRP
leptin
participates in the initiation of eating
lateral hypothalamus
the brain’s mechanism for satiety
ventromedial hypothalamus
What nerve is important in conveying distension of the stomach
vagus nerve
characterized by behaviors of binging and purging
bulimia nervosa
an exaggerated fear of gaining weight, unrealistic perception of weight, and significantly low body weight
anorexia nervose
Located in the postcentral gyrus of the parietal lobes, this area processes bodily sensations like touch, pain, temperature, and proprioception
Primary somatosensory cortex:
Located in Heschl’s gyrus of the temporal lobes, this area receives auditory information
Primary auditory cortex
Located in the occipital lobe, this area processes visual information
Primary visual cortex
A1
Primary auditory cortex
V1
primary visual cortex
