Chapter 2.2 Glossary Flashcards
Acetylchlorine
-neurotransmitter that plays a vital role in the CNS and PNS
-important for muscle control, learning, memory, and attention
-damage will lead to MEMORY loss, possible Alzheimer’s
Action Potential
-temporary shift in the neurons mem. potential causing ion flow
-electrical impulses that move on axon when ions cross the axon membrane
-GENERATED AT AXON HILLOCK
Active transport
-requires energy ATP
-moving against the concentration gradient
-low-high
Afferent neuron
nerve fibers responsible for bringing the outside world info into the brain
Alzheimer’s disease
dementia
-abnormal build up of proteins in and around brain cells causing the brain to shrink.
-no known cause
-affects hippocampus and entorhinal cortex
-disrupts neuron processes
ALS
-nervous system disease that weakens the muscle, impacts movement, twitching, slurred speech, and causes balance issues
-causes are gene mutation, protein mishandling, chemical imbalance of glutamate, and possibly viruses.
-affects brain and spinal cord & voluntary control is affected
Association neuron
“Interneuron”
connects neurons to one another and helps relay information (recieve and transfer)
Axon
long single nerve cell process that conducts impulses away from the body
-passes electrical signals to dendrites of another cell or to its effector
Axon hillock
where the membrane generates nerve impulses, connects soma and axon
Axon terminal
small swellings that are found at the terminal ends of axons. make synaptic connections with other nerve cells
Bipolar neuron
has two extensions (one axon and one dendrite)
found in retina, roof of nasal cavity, and inner ear
calcium ion
involved in electrical synapses.
when calcium ions enter the electrical syn. the cell initiates a signal. causes synaptic vesicles to fuse with presynaptic membrane
triggers synaptic vesicles to release neurotransmitters
Cell body (soma)
maintains cell, and keeps neuron functioning effectively
houses nucleus
contains DNA
cell membrane
semipermeable
surrounds cytoplasm
“barrier”
found in all cells
chemical synapse
chemical signal (neuro trans.) is released from one cell and affects another
common
long
slower than elec.
dendrite
projections of the neuron
recieves signals (electrochem) and travels to soma
depolarization
sudden change in mem. potential
neg-pos interval change
sodium channels open
dopamine
- feelings of pleasure and satisfaction
helpes with movement and motivation
CAN CAUSE ADDICTION
Efferent neuron
carrys motor info. away from CNS to the muscle and the gland of the body for instructions
EKG
Electrocardiogram (HEART)
records elec. signal from heart to check health
Electrodes on skin
electrical synapse
connection in which ions pass directly from one cell to the next via protein channels
-involves depolarization
endorphins
released during exercise, pain, excitement
-well being, euphoria,
Foods ^
enkephalins
involved with pain perception, movement, mood, behavior, reduces impact of pain
epilepsy
causes:stroke, head injury, infection, abuse, birth issues, genes
CNS affected since there is a disruption of electrical activity
seizures (weird odors) -10 year old boy
epinephrine
adrenaline
Fight or flight
produced in exciting situations
stimulates heart rate
–leads to greater awareness and physical capability ( serial killer is chasing you)
EPSP Excitatory postsynaptic potential
more likely to fire an action potential
result of activation of ligland gland
Excitatory
the effect a substance has on a nerve cell
makes cell able to receive important information
exocytosis
release contents to mediate functions
-release of neurotrans.
-release of hormones
- cells move materials from one cell to extracellular fluid
GABA gamma aminobutyric acid
-inhibitory neurotrans. brain
-calms firing nerves to CNS
-high levels= focus and relaxation, low levels = anxiety
-imp. for motor control and vision
Gap junction
mol. like AP diffuse through Gap Junction pores in ELECTRICAL SYNAPSES current passes from cll to cell
glial cell
-regulates nerve firing
-involved in early brain development
-immune responses
-provide supporting functions to the nervous system
glutamate
-most common neurotransmitter
- involved with cognitive function, memory, learning
-regulates brain development and nerve contracts
graded potential
changes membrane potential that vary in response to stimulus
-causes depolarization
histamine
-acts as a neurotrans
-allergic reactions
-response to pathogens
huntington’s disease
symptoms:
depression, mood swings, stumbling, memory loss, involuntary movement of the hands and feet “dance like”
cause: gene mutation in huntingtin
affects the basal ganglia, and cortex and cognitive functions
hyperpolarization
change in cell mem. potential
MORE NEG.
-opposite of depolarization
impulse
-signal
-travels length of nerve fiber
ENDS WITH RELEASE OF NEUROTRANS.
inhibitory
angent slows and interferes with chemical action
regulates
Interneuron
CNS
connects neurons to one another to transfer info.
“the connectors”
involuntary action
takes place ithout concious decision
FASTER THAN VOLUNTARY
ISPS
inhibitory postsynaptic potential
less likely to fire an action potential
ligand gate channel
“ionotropic receptors”
-binds neurotransmitters and opens when ligand binds
CHANNELS THE OPEN OR CLOSE IN RESPONSE TO CHEM MESSAGE
membrane potential
a potential gradient
-forces ions to passively move in 1 direction
Monosynaptic reflex
reflex that provides direct communication with sensory and motor neurons that are involved with the muscle
motor neuron
controls vol & invol movements of the effector muscles and glands
-upper and lower responsible for movement, both work together
multiple sclerosis
disorder in which the body’s immune system attacks the myelin sheaths of neurons
NO KNOWN CAUSE
-fatigue, vision, pain, depression, unsteadiness
CNS is affected
multipolar neuron
single axon with many dendrites
++transfer the MOST info between cells
myelin sheath
insulating layer that forms around nerves
-made of protein and fatty substance
-allows for quick transmission of signals
neuron
info messengers
uses elec. and chem. signals to transfer info.
neurotransmitters
chemical messengers
-released from synaptic vesicle into synapse by neurons
nodes of ranvier
myelin sheath gapps
allow the regeneration of a fast electrical impulse ~axon
norepinephrine
neurotransmitter/ hormone
FIght or flight
used to increase and maintain blood pressure
Nucleus
me. bound structure found in the soma
contains nucleolus and chromosomes
oligodendrocyte
myelinating cells - CNS
enables fast saltatory impulse propagation
parkinson’s disease
loss of nerve cells in substantia, that slowly break down and die
looses the ability to produce norepinephrine which controls various body functions
tremor, slow movements, speech and writing worsen, balance issues
passive transport
membrane transport that does not require energy, it relies on the second law of thermodynamics
polysynaptic reflex
interneurons involved in controlling reflex between afferent and efferent signals
postsynaptic neuron
postsynaptic is a cell that receives information via chemical signals
potassium channels
control transport of potassium ions efflux from and influx into cells
K+ monoatomic monocation from potassium
helps nerve function, fluid balance, and muscle contraction
potassium ion
presynaptic neuron
nerve cell that releases neurotransmitters into synapse
receptor cells
proteins inside or on the surface of a cell which receive signals.
-allows change of activity of a cell
receptors
proteins inside/on the surface of a cell which receive signals.
reflex
protect body from potential harm
involuntary response to stimulus
reflex arc
nerve pathway involved with a reflex action
refractory period
time in which a nerve cell is UNABLE to find an action potential TOWARDS END
repolarization
change in mem potential that returns it to neg. value after depolarization
resting potential
ground state
for trans mem voltage
schwann cells
glial cell that surrounds neuron
myelinating cell-PNS
supports cell of peripheral neurons
secondary messengers
response to exposure to extracellular signaling mol.
intracellular signal ing mol. related
sensory neuron
nerve cell activated by response to enviornment
seratonin
chem. carries messenger between nerves and brain throughout the body
Sodium channels
Na+
resiting potential
generation and propagation of action potentials
sodium ion
helps body keep balance of fluids
Homeostasis
sodium potassium pump
maintains asmotic equilibrium and membrane potential in cells
stimulus
detected by receptors on skin
outside change in environment that causes a sensory reaction
substance
a kind of matter with uniform properties (MO)
summation
presynaptic neuron fires repeatedly at a high rate
synaptic cleft
excitatory and inhibitory postsynaptic currents
gap between pre and post synaptic cells
threshold
membrane voltage that must be reached in excitable cell -depolarization for action potential
unipolar neuron
cell body with one axon which extends into dendrites
vesicles
with in/ outside a cell that consists of cytoplasm enclosed by a liquid bilayer
voltage gated calcium channels
Ca+ depolarize membrane potential for excitability ACTION POT.
