Nervous System Flashcards chapter 1 module 1

Flashcards generated from lecture notes on the nervous system.

What are the two main cell types in the nervous system?

Neurons and glia.

What is the function of a neuron?

To transmit electrical and chemical signals through the nervous system.

What is the function of glial cells?

To support, insulate, nourish, and protect neurons.

What are dendritic spines?

Small protrusions on dendrites where synaptic input is received.

What is myelin and what cells produce it?

A fatty insulation around axons; produced by oligodendrocytes in the CNS and Schwann cells in the PNS.

What is the axon hillock?

The site near the soma where action potentials are initiated.

What is the theory of dynamic polarization?

Information flows from dendrites → soma → axon.

What is an action potential?

A rapid, all-or-none electrical signal that travels along the axon.

What encodes stimulus intensity in neurons?

The frequency of action potentials.

What are graded potentials?

Variable-strength membrane potential changes, such as synaptic or receptor potentials.

What is synaptic transmission?

Communication between neurons via neurotransmitter release across a synapse.

What are excitatory and inhibitory inputs?

Excitatory inputs promote action potentials; inhibitory inputs suppress them.

What is a neural circuit?

A network of interconnected neurons working together to perform a specific function.

What is a monosynaptic reflex?

A reflex involving one synapse between a sensory and motor neuron (e.g., knee-jerk).

What is a disynaptic circuit?

A circuit with two synapses, often involving an interneuron.

What are afferent and efferent neurons?

Afferent = sensory (toward CNS); Efferent = motor (away from CNS).

What are interneurons?

Neurons that connect other neurons, often within a localized region.

What is a common circuit motif called feedforward excitation?

A chain of excitatory neurons transmitting information in one direction.

What is the Brainbow technique used for?

Visualizing individual neurons with distinct fluorescent colors.

What is optogenetics?

A method to control neuron activity using light-sensitive ion channels.

What is calcium imaging?

A technique to monitor neuronal activity by detecting calcium ion changes.

What is connectomics?

The comprehensive mapping of neural connections in the brain.

What are the five levels of analysis in neuroscience?

Molecular, cellular, circuit, systems, and behavioral/cognitive.

What does neural plasticity mean?

The brain's ability to change its structure and function in response to experience.

What are fixed action patterns?

Innate, stereotyped behaviors triggered by specific stimuli (releasers).

What is the significance of twin studies in neuroscience?

They help estimate heritability and the contributions of genetics vs. environment.

What is heritability?

The proportion of variation in a trait due to genetic factors.

Soma

Cell body containing nucleus.

Axon

Long projection for transmitting signals.

Dendrites

Branching processes for receiving signals.

Presynaptic terminals

Found at the ends of axons, release neurotransmitters.