Neurotransmission & Neurophysiology Flashcards
What is soma? What does it have?
the cell bodies of neurons
nucleus, other organelles and protein synthesis center
What do axons do? What is it covered with?
transmit information among neurons
myelin sheath
What is the pathway of axon transmission?
from cell bodies down through axons to pre-synaptic terminal
What is it special about myelin sheath? What does it do?
its fatty substance
help axons transmit electrical signals at higher speed
What type of cells dominate in the CNS?
glia
Types of glia cells
microglia and macroglia
microglia cells
phagotic cells that respond to injury/ injetion
What are types of macroglia? and each function
Oligodendrocyte - produce myelin sheath in CNS
Schwann cells - produce ____ in PNS
Astrocytes - support endothelial cells that form blood-brain barrier
What other functions of glia cells?
nutritive support
facilitate neuron migration during development
clearance of neurotransmitter at synaptic cleft
Types of membrane potentials
resting membrane potentials
graded potentials
action potentials
What is the voltage value at resting membrane potential?
What is resting membrane potential?
~65mV
its the membrane potential of inactive neurons
What happens to ion concentrations in resting membrane potential? What specific pump/ channel that helps to achieve this?
they are in equilibrium
Na+/ K+ pump
what are 2 type of cells in nervous system?
neuron & glia
What does Na+/K+ do?
maintain resting membrane potential by moving 3Na+ out for 2K+ in
What determine the ionic equilibrium potential?
the chemical forces
electrical forces
What is the electrical force in ion equilibrium potential?
the distribution of positive and negative charges across membrane
What is the chemical forces in ionic equilibrium potential?
the concentration gradients of specific ions
what does the -65mV mean?
it means that inside of neuron has a charge of -65mV relative to the outside of cell
what is the character of amplitude in graded potential?
Amplitude varies which decreases with distance from the source
What are types of graded potentials?
receptor potentials
synaptic potentials
receptor potentials
synaptic potentials
change in resting membrane potential due to the external stimuli (light, sound, touch)
changes in membrane potentials of the post-synaptic neuron due to activation of pre-synaptic
What is action potentials?
Where is the action potential generated?
axon hillock
the electrical signals that rise and fall, following trajectory
Threshold potential
the membrane potential at which graded potentials have to pass in order to generate action potentials
How does the change in membrane potential happen?
due to the imbalance of ion concentrations btw inside and outside of membrane
What types of channels that aid the imbalance of ion concetrations occur?
voltage-gated ion channels
ligand-gated channels
voltage-gated ion channels
ligan-gated channels
the channels that open/close in respond to electrical signals
______ in response to substrate
