Neurons, Neurotransmitters & the Nervous System

These flashcards cover key vocabulary and concepts related to neurons, neurotransmitters, and the nervous system.

Nervous System

A network of billions of cells in the brain and body responsible for all aspects of what we feel, think, and do.

Central Nervous System

The part of the nervous system that consists of the brain and the spinal cord.

Peripheral Nervous System

The part of the nervous system that enables nerves to connect the central nervous system to the skin, muscles, organs, and glands.

Neuron

The basic units of the nervous system that receive, integrate, and transmit information.

Dendrites

Branchlike extensions of the neuron with receptors that detect information from other neurons.

Soma (Cell Body)

The part of the neuron where information from thousands of other neurons is collected and integrated.

Axon

The long, narrow outgrowth of a neuron that enables it to transmit information to other neurons.

Terminal Buttons

Parts of the neuron at the end of the axon that release chemical signals into the synapse.

Synapse

The site of communication between neurons through neurotransmitters.

Action Potential

The neural impulse that travels along the axon and causes the release of neurotransmitters.

Voltage-Gated Sodium Channels

Ion channels that open rapidly in response to depolarization, allowing Na⁺ influx.

Sodium-Potassium Pump

A membrane protein that uses ATP to actively transport sodium ions out of the cell and potassium ions into the cell.

Neurotransmitters

Chemical substances that carry signals from one neuron to another.

Excitatory Signals

Signals that increase the likelihood that a neuron will fire an action potential.

Inhibitory Signals

Signals that decrease the likelihood that a neuron will fire an action potential.

Acetylcholine (ACh)

A neurotransmitter involved in muscle contraction, learning, memory, and autonomic nervous system regulation.

Norepinephrine (NE)

A neurotransmitter that increases alertness and attention, and raises heart rate and blood pressure.

Serotonin

Often called the 'feel-good chemical,' it regulates mood, sleep, and appetite.

Dopamine

A neurotransmitter involved in reward, motivation, movement control, and learning.

GABA

The main inhibitory neurotransmitter that reduces neuronal firing and helps regulate anxiety and sleep.

Glutamate

The main excitatory neurotransmitter that increases neuronal firing and is key for learning and memory.

Endorphins

Natural painkillers that reduce perception of pain and create feelings of pleasure.

Endocrine System

A communication system that uses hormones to influence thoughts and actions.

Hormones

Chemical substances released from endocrine glands that travel through the bloodstream to target tissues.