CH2 Flashcards
contains the cell body, nucleus and other organelles; all proteins, receptors, are made here and transported to more distant targets
cell body / soma
extensions that receive information
dendrites
extension that conducts electrical signals from the cell body to the terminal boutons; may have multiple projections sites
axon
not excitable cells, but play key roles in influencing neural action and its transmission (structural support of ion concentrations, reuptake, etc.)
glial cells
main integrating/processing neurons of a brain region; axons project out of the region in which the neuron resides and/or to local neurons within the same region
projection/principle neurons
neurons with many dendritic spines
striata’s medium spiny neurons
any neuron that are in between sensory and motor neurons; cells whose axons remain within a particular brain regions that can connect to projection neurons and other inter neurons
interneurons
interneurons are typically ____ than projection neurons, are usually ______, using ____ or ____ as a NT, and regulate patterns of activities in large ______. Excitatory neurons often can connect to both inhibitory interneurons and other excitatory cells via _____
smaller, inhibitory, ACh, GABA, networks, collaterals
Initial sites of action of neurotransmitters (or drugs)
receptors
______, _____, _____ and ____ ions are needed for neuron function and must be in specific concentrations for the cell to fire
Na+, Ca2+, K+. Cl-
channels that are normally closed and open for a brief period of time in response to specific stimuli before closing
gated channels
ion channels that open when electrical potential across the membrane is altered
voltage gated ion channel
channels that open when a ligand binds to a receptor
ligand gated ion channel
special case of ligand gated channel activated by attachment of a phosphate group on the intracellular side of the receptor
second messenger
Some channels, such as the _______ receptor, are both ligand and voltage gated
NMDA glu
The resting membrane potential inside the cell is ______, driven primarily by higher concentration of positively charged ions _____, _____ and _____ outside the cell, and higher concentration of negatively charged ions _______ inside the cell
negative, Na+, K+, Ca2+, intracellular proteins
Non gated ____ channels always stay open, allowing most positvely charged K+ into the cell through ____ _____ and _____. However, voltage gated ______ channels are closed at rest. The result is a resting potential of _____, where K+ is balanced in the two factors driving it in and out of the cell
K+, electrical attraction, diffusion, Na+, -70mV
occurs when a neuron depolarizes to the threshold of -50mV
action potential
The 4 stages of an action potential
- depolarization causes voltage gated Na+ to open, and Na+ enters (+45mV), 2. action potential causes voltage gated K+ channels to open, and K+ exits the cell 3. Na and K channels both close 4. Na/K pump puts the ion distribution back in balance via active transport, to maintain resting potential
synaptic inputs that cause excitatory post synaptic potentials (EPSPs or IPSPs)
local potentials
local potentials are _____ meaning that a larger stimulus will provide a greater magnitude of hyperpolarization or depolarization. Several small local potentials can add up to larger changes in membrane potential. In contrast, action potentials are ______ (size is unrelated to stimulation) Many NTs and drugs alter neural activity by modulating the impact of inhibitory/excitatory inputs or changing cell _____. Local potentials are generated on the dendrites and _____. They ____ rapidly as they travel along the cell membrane
graded, all-or-none, excitability, cell body, decay
the system that controls voluntary muscles, delivers sensory input to the brain
somatic system
regulates the internal environment by innervating smooth muscles (intestine, bladder) cardiac muscles, and glands (adrenal, salivary etc.)
autonomic system
fight or flight system that dominates during times of stress, excitement and exertion; increases heart rate, blood pressure, blood flow, adrenaline secretion
sympathetic division
dominated when energy reserves can be conserved; increases salivation, digestion, storage of glucose, nutrients, slows heart rate, decreases respiration
parasympathetic division
Many psychoactive drugs affect ___and ____ which are used by ANS neurons, and cause numerous side effects
ACh, NE
The spinal cord sends ___ inputs to the sympathetic ganglia and _____ ____, typically being ______ and act on ____ receptors. Sympathetic ganglia then send ____ inputs to the organs , and this is also secreted into the blood from the _____ gland. NE can be excitatory or inhibitory depending on the receptor ______.
ACh, adrenal glands, excitatory, nicotinic, NE, adrenal, subtype
Drugs that increase NE activity typically _______ sympathetic activation. Drugs that increase ____ release or stimulate nicotinic receptors (ionotropic) , can _____ sympathetic functioning (ex. nicotine)
increase, ACh, increase
The spinal cord projects to parasympathetic ganglia that send short projections to the glands. They exert their effects via the _______ ACh receptors (g coupled). Parasympathetic system uses ACh exclusively
muscarinic
Muscarinic _____ reduce parasympathetic function, resembling sympathetic activation, while ____ do the opposite
antagonist, agonists
neurotransmitters are often ____ in function to maintain a balance (opposite to hormones) and ___ ___ quickly
localized, broken down
convert physical stimuli in the world around us and in our internal environment into an electrical signal and transmit this information to circuits of interneurons
sensory neurons
direct a biobehavioral response appropriate for the situation
motor neurons
