Nervous System Overview

These flashcards cover key concepts and terminology related to the structure and function of the nervous system, including divisions, types of neurons, and their roles.

What are the two main divisions of the nervous system?

The central nervous system (CNS) and the peripheral nervous system (PNS).

What does the central nervous system consist of?

The brain and spinal cord.

What is the primary function of sensory neurons?

To monitor external and internal environmental conditions and send this information to the central nervous system.

What are the divisions of the peripheral nervous system?

Cranial nerves, spinal nerves, and ganglia.

What are the two types of sensory neurons?

Somatic sensory neurons and visceral sensory neurons.

What is the main role of motor neurons in the nervous system?

To transmit impulses from the central nervous system to effector organs.

What is the difference between somatic and autonomic motor systems?

Somatic motor system is voluntary and innervates skeletal muscle, while autonomic motor system is involuntary and innervates smooth muscles, cardiac muscles, and glands.

What are the two subdivisions of the autonomic nervous system?

The sympathetic division and the parasympathetic division.

What is the role of astrocytes in the central nervous system?

To provide structural support for neurons, regulate neurotransmitter levels, and form the blood-brain barrier.

What are the characteristics of neurons?

Neurons exhibit extreme longevity, are non-dividing after fetal development, and have a high metabolic rate.

What is the function of oligodendrocytes?

To form the myelin sheath around axons in the central nervous system.

How does saltatory conduction differ from continuous conduction?

Saltatory conduction occurs in myelinated axons and allows the action potential to jump between nodes, making transmission faster, while continuous conduction occurs in nonmyelinated axons and conducts the impulse along the entire axon length.

What is a nerve?

A parallel bundle of axons in the peripheral nervous system.

Define a monosynaptic reflex.

A reflex arc that involves a single synapse between a sensory neuron and a motor neuron.

What is a polysynaptic reflex?

A reflex arc that involves one or more interneurons between the sensory neuron and motor neuron.