*Week 2: Review Package

Central Nervous System (CNS)

Consists of the brain and spinal cord, responsible for processing sensory information and coordinating responses.

Peripheral Nervous System (PNS)

Connects the CNS to limbs and organs; includes sensory and motor divisions.

Neuron

The basic building block of the nervous system, responsible for transmitting nerve impulses.

Neuroglia

Non-excitable supporting cells in the CNS that support and protect neurons.

Astrocytes

Type of neuroglia that supports neurons and regulates the chemical environment.

Oligodendrocytes

Neuroglial cells in the CNS that myelinate axons to speed up nerve impulse conduction.

Graded Potentials

Changes in membrane potential that vary in strength and can lead to action potentials.

Action Potential

A rapid change in membrane potential that occurs when a neuron reaches the threshold voltage.

Depolarization

The process of changing a neuron's membrane potential to become more positive.

Repolarization

The process of restoring the membrane potential to a negative value after depolarization.

Absolute Refractory Period

The period during which a neuron is unable to fire another action potential, regardless of stimulus strength.

Relative Refractory Period

The time after an action potential when a neuron can fire again, but only with a stronger than usual stimulus.

Multipolar Neuron

A neuron with multiple dendrites and a single axon; the most common type in the CNS.

Bipolar Neuron

A type of neuron with one dendrite and one axon, often found in sensory systems.

Unipolar Neuron

A neuron with a single process extending from its cell body, primarily found in sensory pathways.

Excitatory Postsynaptic Potential (EPSP)

A depolarizing potential that makes a neuron more likely to fire an action potential.

Inhibitory Postsynaptic Potential (IPSP)

A hyperpolarizing potential that makes a neuron less likely to fire an action potential.