Neuron Structure and Synaptic Summation - Chapter 2

Vocabulary flashcards covering neuron structure (cell body, organelles) and synaptic summation (EPSP, IPSP, depolarization, etc.).

Neuron

A nerve cell that transmits information via electrical impulses and chemical signals.

Motor neuron

A neuron that carries commands from the nervous system to muscles and organs.

Soma (Cell Body)

The cell body of a neuron; contains the nucleus and other organelles; the metabolic center of the neuron.

Nucleus

The organelle that houses the cell's genetic material and acts as the control center of cellular activity.

Membrane

The phospholipid bilayer that encloses a cell and regulates what enters and leaves.

Cytoplasm

The jelly-like interior of a cell where organelles reside and metabolic processes occur.

Organelles

Membrane-bound subunits inside a cell that perform specific functions.

Membrane potential

The electrical potential difference across a cell membrane, used to generate and propagate neural signals.

Millivolts (mV)

A unit of electric potential equal to one-thousandth of a volt; used to express membrane potential.

EPSP (Excitatory Postsynaptic Potential)

A depolarizing postsynaptic potential that increases the likelihood of an action potential.

IPSP (Inhibitory Postsynaptic Potential)

A hyperpolarizing postsynaptic potential that decreases the likelihood of an action potential.

Depolarization

A decrease in the magnitude of the resting membrane potential (the interior becomes less negative), increasing firing probability.

Hyperpolarization

An increase in membrane potential negativity (interior becomes more negative), reducing firing probability.

Resting potential

The baseline membrane potential of a neuron when it is not firing, typically around -70 millivolts.

Threshold

The membrane potential that must be reached to trigger an action potential.

Action potential

A rapid, transient spike in membrane potential that travels along the neuron when the threshold is reached.

Spatial summation

The integration of impulses arriving at multiple locations on a neuron, influencing the net membrane potential.

Temporal summation

The integration of impulses arriving in rapid succession over time, influencing the net membrane potential.

Excitatory input

Input that depolarizes the neuron, making an action potential more likely.

Inhibitory input

Input that hyperpolarizes the neuron, making an action potential less likely.

Neuron

A nerve cell that transmits information via electrical impulses and chemical signals.

Motor neuron

A neuron that carries commands from the nervous system to muscles and organs.

Soma (Cell Body)

The cell body of a neuron; contains the nucleus and other organelles; the metabolic center of the neuron.

Nucleus

The organelle that houses the cell's genetic material and acts as the control center of cellular activity.

Membrane

The phospholipid bilayer that encloses a cell and regulates what enters and leaves.

Cytoplasm

The jelly-like interior of a cell where organelles reside and metabolic processes occur.

Organelles

Membrane-bound subunits inside a cell that perform specific functions.

Membrane potential

The electrical potential difference across a cell membrane, used to generate and propagate neural signals.

Millivolts (mV)

A unit of electric potential equal to one-thousandth of a volt; used to express membrane potential.

EPSP (Excitatory Postsynaptic Potential)

A depolarizing postsynaptic potential that increases the likelihood of an action potential.

IPSP (Inhibitory Postsynaptic Potential)

A hyperpolarizing postsynaptic potential that decreases the likelihood of an action potential.

Depolarization

A decrease in the magnitude of the resting membrane potential (the interior becomes less negative), increasing firing probability.

Hyperpolarization

An increase in membrane potential negativity (interior becomes more negative), reducing firing probability.

Resting potential

The baseline membrane potential of a neuron when it is not firing, typically around -70 millivolts.

Threshold

The membrane potential that must be reached to trigger an action potential.

Action potential

A rapid, transient spike in membrane potential that travels along the neuron when the threshold is reached.

Spatial summation

The process by which a neuron combines excitatory or inhibitory postsynaptic potentials (EPSPs or IPSPs) that originate from different locations on the dendrites or cell body at the same time. If the summed potential reaches the threshold, an action potential is triggered.

Temporal summation

The process by which a neuron combines excitatory or inhibitory postsynaptic potentials (EPSPs or IPSPs) that arrive at the same synapse in quick succession. If the inputs arrive fast enough before previous potentials decay, their effects can summate to reach the threshold and trigger an action potential.

Excitatory input

Input that depolarizes the neuron, making an action potential more likely.

Inhibitory input

Input that hyperpolarizes the neuron, making an action potential less likely.

Ionotropic Receptor

Ligand-gated ion channels that open rapidly upon neurotransmitter binding, allowing ion flow and causing fast postsynaptic potential changes.

Metabotropic Receptor

G-protein coupled receptors that initiate intracellular signaling cascades upon neurotransmitter binding, leading to slower, longer-lasting postsynaptic effects.

Neural Network

A complex system of interconnected neurons that process and transmit information, forming the basis of brain function and cognitive abilities.