Exam 4 Flashcards
Define neuronal pool
Single presynaptic fiber branches and synapses with several neurons in a pool
what are the types of neuronal pools?
Diverging
Converging
Reverberation
Parallel after-discharge
which type of neuronal pool has one input and outputs?
diverging
what type of neuronal pool is many inputs and outputs?
converging
what type of neuronal pool are many signals traveling through a chain of neurons each feeding back previous neurons?
reverberating
what type of neuronal pools are signal stimulates neurons in parallel arrays that eventually converge on a single output cell?
parallel
What is the neurotransmitter used in autonomic neurons?
Autonomic pathways release both acetylcholine (ACh) and norepinephrine (NE) as neurotransmitters
What is the neurotransmitter used in somatic neurons?
somatic pathway’s motor neurons just use ACh.
what is released at neuromuscular junctions by some ANS neurons & cNS neurons?
acetylcholine
what is the Neurotransmitter regulating mood and sleep?
seretonin
what is found in substantial nigra
and often associated with Parkinson’s disease?
dopamine
what are the steps of the action potential?
- Resting state: no ions move through voltage-gated channels
- Depolarization: is caused by Na+ flowing into the cell
- Repolarization: is caused by K+ flowing out of the cell
- Hyperpolarization: is caused by K+ continuing to leave cell
what is cerebrospinal fluid?
Is a Watery solution formed from blood plasma
what does the choroid plexus produce?
Cerebrospinal fluid
what is the circulation of cerebrospinal fluid?
CSF flows through the ventricles and into the subarachnoid space via the median and lateral apertures
CSF flows through the subarachnoid space
CSF is absorbed into the dural venous sinuses via the arachnoid villi
What are the cerebrospinal functions?
Give buoyancy to CNS structure
Protects CNS from blows and other trauma
Nourishes brain and carries the chemical signal
what are bundles of neuron processes in CNS?
tracts
what are bundles of neuron processes in PNS?
nerve
What lies along nerves in PNS and are Cell bodies together?
Ganglia
What are the functions of the nervous system?
Sensory input: information gathered by sensory receptors about internal and external changes
Integration: processing and interpretation of sensory input
Motor output: Activation of effector organs( muscles and glands) produces a response
What are the small cells that surround and wrap delicate neurons?
Neuroglia
What are the neuroglia types?
Astrocytes(CNS)
Microglial cells (CNS)
Ependymal cells (CNS)
Oligodendrocytes (CNS)
Satellite cells(PNS)
Schwann(PNS)
What are the most abundant neuroglia cells that :
Guide the migration of young neurons (cling to neurons, synaptic endings, and capillaries)
Support and brace neurons
Controls chemical environment around neurons
Astrocytes(CNS)
What is the neuroglia cell type that migrates toward injured neurons?
Microglial cells (CNS)
what neuroglia cell type forms a permeable barrier between cerebrospinal fluid (CSF) in cavities and tissue fluid bathing CNS cells?
Ependymal cell
what neuroglia cell type forms insulating myelin sheaths thicker nerve fibers(helps transmit the electricity)?
Oligodendrocytes (CNS)
what neuroglia cell type forms insulating myelin sheaths thicker nerve fibers(helps transmit the electricity)?
Oligodendrocytes (CNS)
What type of neuroglia cells is surrounding neuron cell bodies in PNS and are Functional similar to astrocytes of CNS?
Satellite cells(PNS)
What type of neuroglia cells have similar functions as oligodendrocytes and Individual cells?
Schwann(PNS)
What Lie between motor & sensory neurons, shuttle signals through CNS pathways
and are mostly found in CNS?
interneurons
What is a Whitis protein-lipoid substance?
myelin
What is the function of myelin?
Protects and electrically insulates the axon
Increases speed of nerve impulse transmission
How does myelin impact the conduction rate?
Unmyelinated fibers conduct impulses more slowly
what conduct impulses from the CNS to effectors?
motor neurons
What conducts impulses from CNS to skeletal muscle?
somatic sensory fibers
What Nervous system regulates smooth muscle cardiac and glands?
Autonomic nervous system
What conveys impulses from skin, skeletal muscles, and joints to CNS?
somatic sensory fibers
What conveys impulses from visceral organs to CNS?
Visceral sensory fibers
What does the Central nervous system consist of?
brain & spinal cord
Integrative and control centers
What does the Peripheral nervous system consist of?
Cranial nerves and spinal nerves
Communication between the CNS and the rest of the body
What does the sensory afferent division consist of?
Somatic and visceral sensory nerve fibers
Conduct impulses from receptors to the CNS
What does the motor(efferent) division contain?
Motor nerve fibers
Conducts impulses from the CNS to effectors (muscles and glands)
what does the autonomic nervous system do?
Visceral motor(involuntary)
Conducts impulses from the CNS to cardiac muscles, smooth muscles, and glands
What does the sympathetic division do?
Mobilizes body systems during activity
What does the parasympathetic division do?
Conserves energy
Promotes housekeeping functions during rest
What responds to stretch in skeletal muscles, tendons, joints, ligaments, and connective tissue?
Proprioceptors
What are thermoreceptors?
Sensitive to changes in temperature
what allows for relaying information derived from blood pressure within the autonomic nervous system?
Baroreceptors
what responds to chemicals (e.g., smell, taste, changes in blood chemistry?
Chemoreceptors
what are the reflex arc processes?
1.Receptor: site of stimulus action
- Sensory neuron: transmits afferent impulses to CNS
3:Integration center: either monosynaptic or polysynaptic region within CNS
4.Motor neuron: conduct efferent impulses from integration center to effector organ
5.Effector: muscle fiber or gland cell that responds to efferent impulses by contracting or secreting
What does the ventral root contain?
Axons for motor neurons
- cell bodies of motor neurons are in the gray matter of the spinal cord - anterior horn
- merge w/dorsal root to form a spinal nerve
what does the dorsal root contain?
Axons for sensory neurons
- merges with w/ventral root to form the spinal nerve
what does the cauda equina contain?
“Horses Tail”
- spinal nerves exiting off the end of the spinal cord
what does the filum terminal do?
anchors conus medullaris to the coccyx
What are acquired reflexes?
Learned reflexes result from practice or repetition
what activates visceral effectors (smooth or cardiac muscle or glands)?
Autonomic reflexes
What is an innate reflex?
Genetically determined
What control actions of smooth and cardiac muscles and glands?
Visceral reflex
What does the somatic activate?
Activate skeletal muscles
what is Transection between T1 and L1?
paraplegia
Which layer is the strongest meninx, Two layers of fibrous connective tissue (around the brain) separate to form dural venous sinuses.
dura mater
What is the Middle layer with web-like extensions Separated from dura mater by subdural space?
Arachnoid mater
What is the innermost layer, and delicate vascularized connective tissue that clings tightly to the brain?
Pia mater
What is the area of skin innervated by cutaneous branches of a single spinal nerve?
Dermatome
What are the nerves serving the upper and lower limbs?
Cervical enlargement
What Innervates hamstrings muscles adductor magnus?
Sciatic nerve
What does the stretch reflex maintain?
Maintains muscle tone in large postural muscles and adjusts it reflexively
What does the spinothalamic tract do?
Transmit pain temperature coarse touch and pressure impulses within the lateral spinothalamic tract
What conveys information about muscle or tendon stretch to the cerebellum?
(Ventral and dorsal tracts)
Spinocerebellar tract
What tract maintains balance?
Vestibulospinal tract
what tract controls flexor muscles?
Rubrospinal tract
what is the cerebellum function?
Allows smooth, coordinated movements
Role in thinking language and emotion
Where is the thalamus located?
superior to the hypothalamus.
what is the thalamus function?
Motor Control
Receives Auditory, Somatosensory and Visual Sensory Signals
Relays Sensory Signals to the Cerebral Cortex
What is the function of the medulla oblongata?
Controls autonomic functions
Relays nerve signals between the brain and spinal cord
Where is the Medulla oblongata located?
The medulla oblongata is the lower portion of the brainstem.
It is inferior to the pons and anterior to the cerebellum.
What is the function of the corpus callosum?
connects the left and right hemispheres of the brain
Where is the corpus callosum located?
the corpus callosum is a thick band of fibers located between the cerebral hemispheres
What is the Diencephalon location?
A region of the forebrain located below the thalamus, forming the basal portion of the diencephalon
What is the function of the Diencephalon?
regulate body temperature, some metabolic processes, and govern the autonomic nervous system.
What is the function of the hypothalamus?
Regulates body temperature
Regulates hunger and satiety in response to nutrient blood levels or hormones
Regulates water balance and thirst
Regulates sleep-wake cycles
Controls endocrine system
Where is the hypothalamus located?
below the thalamus and posterior to the optic chiasma.
what is the pons function?
Arousal
Assists in Controlling Autonomic Functions
Relays Sensory Information between the Cerebrum and Cerebellum
Sleep
Where is the pons located?
is the portion of the brainstem that is superior to the medulla oblongata.
What are functions of the midbrain?
Controls responses to the sight
Eye movement
Pupils dilation
Body movement
Hearing
Where is the midbrain located?
between the forebrain and brainstem
What are the upside-down characters that represent contralateral motor innervation of body regions?
Motor homunculi
What are the upside-down characters represent contralateral sensory input from the body?
sensory homunculi
What lobe is the visual processing center?
occipital lobe
Where is the occipital lobe located?
dorsal to the brain
What is the function of the frontal lobe?
Controls personality and communication (important cognitive skills)
where is the frontal lobe located?
anterior to the parietal lobe, superior & anterior to the temporal lobe
What is the function of the temporal lobe?
primary auditory perception
where is the temporal lobe located?
lateral to the brain
What are Paired anterior nuclei &Olfactory relay stations?
Mammillary bodies
What is the Stalk that connects to pituitary gland ?
infundibulum
what is the function of Extends from the posterior border and secretes melatonin?
pineal gland
where is the pineal gland?
Base of brain below hypothalamus
what is these functions match with:
Controls learned repetitious or patterned motor skills
Coordinates simulation or sequential actions
Controls voluntary actions that depend on sensory feedback
premotor cortex
What allows conscious control of precise skilled skeletal muscle movements?
Primary Motor Cortex
Suprachiasmatic Nucleus is located:
hypothalamus
What regulates sleep-wake cycles?
Suprachiasmatic nucleus
What regulates sleep-wake cycles?
Suprachiasmatic nucleus
