Lab 1 - Nervous System Flashcards
what do spinal taps diagnose
CNS issues
what type of CNS issues do spinal taps diagnose
meningitis
subarachnoid hemorrhages
encephalitis
Guillain-Barre Syndrome
Multiple sclerosis
what does RMP result from
a difference in charge across the cell membrane
what is the average RMP in a nerve cell
-70 to -90 mV
what are 3 ways to maintain RMP
selective permeability (diffusion)
ion pumps
large anions trapped on the inner surface of the membrane
what is selective permeability (diffusion)
passive leakage of ions through channels - against concentration gradient
where do positive charges accumulate
outside membrane
what is the resting membrane permeable to
K+
what is the resting membrane barely permeable to
Na+, Ca2+, Cl-
what compensates for diffusion leakage
ion pumps
what do ion pumps do
keep concentration of ions remaining relatively constant inside the cell
ratio of Na+/K+ pump
3 Na+ out
2 K+ in
how much energy do ion pumps require
lots - up to 40% of available ATP
what are types of large anions that are trapped on the inner surface of the membrane
organic anions mostly in proteins and amino acids
where are large anions found in a higher concentration
inside cell
can large anions pass through membrane freely
no
what are large anions attracted to
outside positive charges
what are excitable cells
cells that can generate electrical impulses (action potentials)
what can excitable cells change
their membrane polarity
how do excitable cells change their membrane polarity
using specialized ion channels with gates that open and close (voltage - gated ion channels)
what is the channel gate controlled by in nerve cells
voltage (voltage-gated ion channels)
what is the position of the gate at rest
closed
why is the gate closed at rest
gate needs stimulation (voltage) to reach threshold provoking the opening of the gate
what is synaptic transmission
continuation of signal between a neuron and the following cell (another neuron or target cell)
what is a neuronal junction
signal transmission between 2 neurons
what is a neuromuscular synapse
signal transmission between a neuron and skeletal muscle cell
what is the cell membrane made up of
phospholipids
what do the phospholipids act as in cell membrane
electric insulator
what is a neurotransmitter
molecule responsible for passing the info
what is the neuromuscular synapse transmitter
Ach
what do neurotransmitters do
convert the electrical signal (AP) into a chemical signal
what is common in neuromuscular synapse to increase surface area
post-synaptic folding
