Chapter Two Flashcards
Central Nervous System
Brain and spinal cord
Peripheral Nervous System
nerves that run throughout your body
Sensory/Afferent neurons
carry information to the brain
Motor/Efferent neurons
carry information away from the brain
Interneurons
make connections within nervous system
Dendrites
receive information
Soma
centralized part; cell body; process information
Axon
send/carry information away from the soma
Terminal buttons
flaring at the end of axon terminal; connects to other cell dendrites all of actions take place here
multipolar neurons
one axon, many dendrites
bipolar neurons
one axon, one stalk on the dendrites
unipolar neurons
one axon that divides after leaving soma
cell membrane
2x liquid layer; semi permeable
cytoplasm
liquid filled with mitochondria
mitochondria
produce energy through ATP
nucleus
contains chromosomes, DNA, and genes
proteins/enzymes
carry things throughout the cell
axoplasmic transport
substances/structures are carried from cell body down the axon through the microtubules –> highway system
anterograde
away from cell body –> axon
retrograde
back toward cell body
Glia
“glue” cells that provide structure, support, and insulation to neurons
Astrocytes
star shaped; house keepers through phagocytosis
Oligodendrocytes
myelinate the CNS; one cell provides myelin for many neuron
Schwann Cells
myelinate the PNS; one cell provides myelin for one neuron
Blood-Brain Barrier (BBB)
allows brain to keep delicate balance of chemicals within it
not permeable to most substances
-lack tiny capillaries of brain
The one weakness in the BBB
area postrema: the part of the brain that induces vomitting
Neural Communication
all neurons send either yes (excitatory) or no (inhibitory) messages
a yes message-excitatory
makes the next cell more likely to have an action potential “gossip”
a no message-inhibitory
makes the next cell less likely to have an action potential “secrets”
Reflex Arc
dorsal in, ventral out pathway;
inhibition comes from the brain in this example
microelectrode
measures membrane potential
resting potential is -70mV
inside the cell is negatively charged compared to the fluid surrounding it
ions
electrically charged particle, inside and outside of the axon
Why is there resting potential?
if there was not, -70mV charge, neurons could not communicate
ion distribution inside/outside of cell
cations
positive
anions
negative
what ions are inside and outside of the cell?
potassium is inside the cell, sodium and chloride are outside of the cell
