Nervous System Flashcards
Functions of the Nervous System
- Maintaining homeostasis
- Receiving sensory input
- Integrating information
- Controlling muscles & glands
- Establishing and maintaining mental activity
Two main divisions of the nervous system?
Central and Peripheral
2 main divisions of Peripheral Nervous
Sensory & Motor Division
Afferent & Efferent
division of the nervous system composed of the brain and spinal cord
CNS
division of the nervous system which consists of the nervous tissue outside the CNS
PNS
____ send electrical messages to other cells
neurons
A ____ is a bundle of many
axons that connects the CNS to sensory receptors, muscles, and glands
nerve
how many cranial nerves are there?
12 pairs (24)
how many pairs of spinal nerves?
31 pairs (62)
has both sensory and motor neurons and contained wholly within the digestive tract
Enteric Nervous System
ENS
2 divisions of the motor division?
Somatic & Autonomic
So anong difference ng Autonomic sa Somatic division?
Somatic targets skeletal muscles & soma = body; whereas Autonomic controls unconscious activities sa body kaya nga Auto = automatic siya wala kang gagawin
2 divisions of the ANS?
Sympathetic & Parasympathetic
A ____ is the junction of a neuron between another cell
synapse
main cells of nervous s’tem that receive stimuli, conduct action potentials, & transmit signals to other neurons
neurons
what receives info from other neurons then transmits it towards the cell body?
short; cytoplasmic extension
dendrite
part of a neuron that sends signals away or toward the CNS
axon
3 types of neurons
pseudo-uni, bipolar, multipolar
type of neuron that is many to one
many dendrites & one axon
plenty receivers one sender
multipolar
type of neuron that has one dendrite & one axon
one is to one
bipolar
type of neuron that has one process from the cell body that extends into 2 branches?
one branch to CNS; another to PNS
psedo-unipolar
Functional types of neurons?
Sensory, Motor, Interneuron
Interneurons conduct potentials within the CNS from one neuron 2 another
Supporting cells of the nervous system are called
Glial cells
major supporting cells in the CNS that stimulate or inhibit signaling activity of neurons
also part of the blood-brain barrier between blood & CNS
Astrocyte
____ line the fluid-filled cavities within the CNS and produces cerebrospinal fluid
lines the venctricles & canals
ependymal cells
immune cells of the CNS
microglia
cells that provide myelin sheath to axons
Oligodendrocytes
gives myelin sheath to axons in the PNS
Schwann cells
support and protection of neurons from heavy-metal poisions
Satellite cells
Myelinated axons appear?
white, gray, or black?
WHITE!
gaps in myelin sheaths are called?
nodes of ranvier
Type of nervous tissue that consists of groups of neuron cell bodies and their dendrites where there is very little myelin
Gray matter
type of nervous tissue that consists of bundles of parallel axons with their myelin sheaths
White matter
Gray matter in the CNS? in the PNS?
cortex, nuclei; ganglion
White matter in the CNS? in the PNS?
nerve tracts; nerves
Two types of Ion channels
Leak channel & Gated channels
types of gated channels
Ligang-gates, voltage-gated, and other gated channels
________ occurs when the membrane potential becomes more positive
depolarization
occurs when the membrane potential becomes
more negative and is the movement of the membrane potential further away from zero
hyperpolarization
Which is more numerous in the inside of the cell? How about the outside?
K+ or Na+
Potassium is higher inside. Sodium is higher outside
the inside of the cell membrane is ____ charged and the outside is ____?
negatively charged or positively charged
inside is negatively charged; outside is positively charged
that is why K+ ions come in. thus, resting membrane potential
what is the small voltage difference that can be measured accross the cell membrane?
potential
plasma membrane is ____ times more permeable to K+ than any other posi-charged ions (Na+)
50-100 more times
When stimulus is applied to a muscle or nerve cell, what channel opens?
Na+ or Sodium channels open
The movement of Na+ into the cell is called____, and causes the cell to become ____, a change called ____.
local current; positive; depolarization
____ of graded potentials occurs when the effects produced by one graded potential combine with the effects produced by a different graded potential elsewhere on the plasma membrane, which could lead to an action potential
Summation
combi of graded potntls frm diff places tht cld lead 2 action potential
Increased permeability of cells to Na+ results to what?
Depolarization
Increased permeability of the membrane to K+ or Cl- results in what?
hyperpolarization
____ is the membrane potential at which voltage-gated Na+ channels open.
when membrane potential reaches this, Na+ channels open
Threshold
REMEMBER!
As long as the Na+ and K+ concentrations remain unchanged across the plasma membrane, all the action potentials produced by a cell are identical. They all take the same amount of time, and they all exhibit the same magnitude
basta pareho Na+ & K+ pareho lang lahat ng action potential na mapproduce
period wherein area on the plasma membrane becomes less sensitive to further stimulation
refractory period
the first part of the refractory period wherein complete insensitivity to another stimulus exists
absolute refractory period
The ____ follows the absolute refractory period and is the time during which a stronger-than-threshold stimulus can evoke another action potential
relative refractory period
saur basically eto yung after ng absolute ref period
A type of stimulus that only produces a graded potential
subthreshold stimulus
A type of stimulus that causes a graded potentital that reaches threshold and results in a single action potential
threshold stimulus
a type of stimulus that is greater than a threshold stimulus and weaker than a maximal stimulus
submaximal
the action potential frequency ____ as the strength of the submaximal stimulus increases
increases or decreases
increases
A type of stimulus that produces a maximum frequency of action potentials
maximal or supramaximal
conduction in unmyelinated axons is called?
continuous
conduction in myelinated axons is called
saltatory conduction
saltare, to leap
conduction in myelinated axons is called
saltatory conduction
saltare, to leap
the cell that transmits the signal towards the synapse is called?
presynaptic cell
the target cell receiving the information is called
postsynaptic cell
summation that occurs when multiple action potentials from separate neurons arrive at the same postsynaptic neuron
spatial summation
from many presynaptic to one postsynaptic
occurs when two or more action potentials arrive in succession at a single presynaptic terminal
temporal summation
one presynaptic to one postsynaptic
3 components of chemical synapse
presynaptic, postsynaptic, synaptic cleft
what can happen to the neurotransmitter once it is on the postsynaptic membrane?
broken down by enzyme
taken back by presynaptic
diffuses out of synaptic cleft
pathway wherein multiple neurons converge upon and synapse with smaller number of neurons
convergent pathway
pathway wherein a smaller number of presynaptic synapse with a larger number of postsynaptic neurons
divergent pathway
where the spinal cord ends
cauda equina
most superficial and thickest of the meninges
dura mater
middle part of the meninges that is very thin and spiderlike
arachnoid mater
deepest of the meninges and is bound very tightly to both the brain and spinal cord
pia mater
layer or space where CSF can be found
subarachnoid space
between arachnoid mater and pia mater
horns of the gray matter in the spine
anterior, posterior, and lateral horns
ventral, dorsal, lateral
center of the spinal cord
central canal
If ____ is to motor, then ____ is to sensory
ventral or dorsal
Ventral root, Dorsal root
basic functional unit of the nervous system
reflex arc
Composition of reflex arc
(1) a sensory receptor, (2) a sensory neuron, (3) an interneuron, (4) a motor neuron, and (5) an effector organ
simplest reflex is called
and example is?
stretch reflex
knee-jerk or patellar reflex is an example
simplest reflex is called
and example is?
stretch reflex
knee-jerk or patellar reflex is an example
type of reflex that prevents contracting muscles from applying excessive tension to tendons
Golgi Tendon Reflex
reflex wherein its function is to remove a limb or a body part from a painful stimulus
withdrawal reflex
3 layers of connective tissue in nerves
Endoneurium, Perineurium, Epineurium
If ____ is the PNS, then ____ is in the CNS
tracts or nerves
Nerves; Tracts
a major branch of a spinal nerve
ramus
rami that innervate most of the deep muscles of the dorsal trunk responsible for moving the vertebral column
Dorsal rami
rami that form intercostal nerves and plexuses
ventral rami
Plexus names of:
C1-C4?
C5-T1?
L1-L4?
L4-S4?
S5&Co?
Cervical
Brachial
Lumbar
Sacral
Coccygeal
nerve responsible for diaphragm contraction
phrenic nerve
cervical plexus
connecs the spinal cord to the cerebrum
has medulla oblongata, pons, and mibdrain w/ reticular formations
brainstem
part of brainstem that is a center for reflex, e.g., heart rate, breathing, vomiting, swallowing
medulla oblongata
part of the brainstem just superior to the medulla oblongata
pons
smallest region of brainstem
serves as visual reflex center and is a part of auditory pathway
midbrain
scatterred throughout brainstem and controls motor, pain perception, and sleep-wake cycle
reticular formation
part of the brain that controls muscle movement and tone; governs balance and involved in learning motor skills
cerebellum
connects the brainstem to the cerebrum
diencephalon
subdivisions of diencephalon
epithalamus
thalamus
hypothalamus
part of the brain that controls perception, thought, and can override most systems
cerebrum
diencephalon region involved in motor function
subthalamus
diencephalon region responsible for emotions through smell and location of the pineal gland
habenula nd pineal gland loc
epithalamus
part of diencephalon responsible for endocrine functions
hypothalamus
the folds in the brain are called? the grooves are called?
folds are gyri, grooves are sulci
Cerebrum Lobes and Functions
Frontal:
Pariteral:
Occipital:
Temporal:
Frontal: motor functions
Pariteral: sensory area
Occipital: visual center
Temporal: auditory and smell; judgement and memory
CSF is produced where and by?
choroid plexus by ependymal cells
where does CSF pass from the lateral to the fourth ventricle?
interventricular foramen or foramen of monro
Passageway of CSF from 3rd to 4th vntricle
cerebral aqueduct
what forms the blood-brain barrier
endothelial, ependymal, and astrocytes
Oh Oh Oh To Touch And Feel Victor’s Good Velvet’s A Heaven
Olfactory, Optic, Oculomotor, Trochlear, Tringeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Accessory, Hypoglossal
smell, vision, eye mvmnt (2), mastication, eye muscle, facial expression
hearing & balance, taste, pharynx palate nd larynx, spinal comp, tongue muscles
Some Say Marry Money But My Brother Says Big Brains Matter More
Sensory, Sensory, Motor, Motor, Both, Motor, Both, Sensory, Both, Both, Motor, Motor
