Unit 4: Neurophysiology Study Guide

Flashcards covering key concepts from the neurophysiology study guide.

What are the three major functions of the nervous system?

Sensory input, integration, motor output.

What does CNS stand for and what are its components?

Central Nervous System; comprises the brain and spinal cord.

What is the role of the PNS?

Peripheral Nervous System; carries information to/from the CNS.

What are the two main divisions of the autonomic nervous system?

Parasympathetic (‘rest/digest’) and sympathetic (‘fight/flight’).

What are the three connective tissue layers surrounding nerves?

Endoneurium, Perineurium, and Epineurium.

How do neurons differ from glial cells?

Neurons are excitable and transmit impulses; glial cells support, protect, and nourish.

Name the types of CNS glial cells.

Astrocytes, Oligodendrocytes, Microglia, Ependymal cells.

What are the two types of PNS glial cells?

Schwann cells and Satellite cells.

List the main parts of a neuron.

Dendrites, Cell body, Axon hillock, Axon, Terminals.

What are the key characteristics of neurons?

Excitable, conductive, long-lived, amitotic, and have high metabolism.

What are the two classifications of neurons?

Functional (sensory, motor, interneurons) and structural (multipolar, bipolar, unipolar).

Define voltage, current, and resistance.

Voltage: potential difference; Current: flow of ions; Resistance: opposition to flow.

What is the resting membrane potential of a neuron?

Approximately -70 mV; maintained by Na+/K+ pump and leak channels.

What stimuli can cause depolarization in neurons?

Chemical, mechanical, light, or voltage change.

What are the steps of action potential?

Depolarization (Na+ in), Repolarization (K+ out), Return to rest (Na+/K+ pump).

How do graded potentials differ from action potentials?

Graded potentials are local and of variable strength; action potentials are all-or-none and travel full length.

What is the refractory period?

The period during which a neuron cannot refire, preventing backward current.

What is the difference between saltatory conduction and unmyelinated conduction?

Saltatory conduction jumps node to node and is faster; unmyelinated conduction is continuous and slower.

What is the sequence of events in synaptic transmission?

Action potential → Ca²⁺ entry → neurotransmitter release → receptor binding → ion channels opening.

What are the parts of a synapse?

Presynaptic neuron, synaptic cleft, postsynaptic neuron.

How is neurotransmitter inactivation achieved?

Through enzymes, reuptake, and diffusion to prevent overstimulation.

What are the two types of summation?

Spatial summation (many neurons) and temporal summation (one neuron repeatedly).

What are the types of neural circuits?

Convergent, divergent, reverberating, and parallel-after-discharge.

Name some common nervous disorders.

Multiple sclerosis, Parkinson’s, Alzheimer’s, Epilepsy.