unit 2 CNS Flashcards
at 4 weeks the human brain is made of 4 regions, what are they?
Forebrain, midbrain, hindbrain, spinal cord
the forebrain is differentiated into these two regions
cerebrum, dienchephalon
the hindbrain is differentiated into these 3 regions
Medulla oblongata, cerebellum, pons
Name the three layers of meninges from innermost to outermost
Pia mater, arachnoid membrane, dura matter
where is cerebrospinal fluid produced?
In the coroid plexuses found within each of the 4 ventricals
How does CSF get into the subarachnoid space?
through apertures in the 4th ventrical
how does CSF escape the subarachnoid space?
through arachnoid villi that protrude into the dural sinus
what are two defining characteristics of CSF when compared to plasma?
CSF has very low protein and no blood cells
The presence of blood or protein in CSF indicates what?
infection
what creates the myelin sheath within the CNS?
oligodendrocytes
________ wrap around capillaries and secrete paracrine factors that promote tight junctions within the CNS
astrocytes
Dural sinus is also called s_________ sinus
superior sagittal sinus
three metabolic quirks of neural tissues
- require a lot of oxygen
- require a lot of glucose
- require a lot of blood
the four sections of the spinal nerves
cervical, thoratic, lumbar, sacral
the sympathetic nerves on the spinal cord are located in a section for the spine called the _____
thoraco-lumbar division
definition of nuclei in the CNS
cluster of synapses
definition of tracts in the cns
bundle of axons
dorsal column transmit information about ________ towards the _______
touch, pressure, proprioception
brain
the spinothalamic tract transmits information about _____
pain and temperature
corticospinal tracts transmit information about ________
voluntary movement
the lateral corticospinal tract control the _____
the ventromedial corticospinal tract control the ______
limbs
trunk muscles
The midbrain is responsible for____
eye movement, visual and auditory reflexes
Pons are responsible for ____
relay station between cerebrum and cerebellum
medulla is responsible for _____
control of many involuntary functions, blood pressure, breathing, swallowing
medulla is the site of _____ for most neurons in the spinal tract
decussation (crossing over)
the cerebellum coordinates _____
movement
diencephalon has four structures
thalamus, pineal gland, hypothalamus, pituitary gland
what does the thalamus do?
relays and integrates sensory information
what does the hypothalamus do?
center for homeostasis
hunger, thirst, autonomic responses, endocrine systems
what does the pineal gland do?
secretes melatonin, involved in circadian rhythms
the four lobes of the cerebrum
frontal, occipital, parietal, temporal
the three regions of cerebral grey matter
basal ganglia, limbic system, cerebral cortex
primary motor cortex is located ____
in the frontal lobe, ridge just anterior to central sulcus
primary somatosensory cortex is located ________
in the parietal lobe, ridge just posterior to the central sulcus
dorsal columns in the spinal cord carry information about _____
touch, pressure, proprioception
spinocerebellar tract carry information about _____
propriocenption (posture, coordination)
spinothalamic tract carry information about ____
pain and temp
corticospinal tract carry information about ____
voluntary movement
the lateral corticospinal tracts control the ____
limbs
a signal controlling the limbs will ____ in the medulla, follow the _____ corticospinal tract, and _____ in spinal grey matter
cross, lateral, not cross
a signal controlling the trunk will ____ in the medulla, follow the _____ corticospinal tract, and _____ in spinal grey matter
not cross, anterior, cross
5 steps of a spinal reflex
- painful stimulus activates receptor
- primary sensory neuron enters spinal cord
- collateral activates ascending pathway for sensation (cc to brain)
- withdrawal reflex
- crossed extensor reflex
_____ substances require a channel to cross the blood brain barrier
hydrophilic / lipophobic
