Nervous System Organization and Function

Flashcards covering key concepts in the organization and functions of the nervous system from the lecture notes.

The two main cell types in nervous tissue are and .

neurons and glial cells.

The central nervous system (CNS) consists of the and .

brain and spinal cord.

Cranial nerves originate from the and spinal nerves originate from the .

brain; spinal cord.

The primary role of glial cells is to __ support and various other functions in the nervous system.

provide.

The division of the nervous system that transmits action potentials toward the CNS is called the __ division.

sensory (afferent).

An action potential is generated when a graded potential reaches __.

threshold.

The two divisions of the autonomic nervous system are the and divisions.

sympathetic; parasympathetic.

In myelinated axons, action potentials propagate by conduction, while in unmyelinated axons they propagate by conduction.

saltatory; continuous.

The part of the neuron that conducts action potentials away from the cell body is called the __.

axon.

The __ period is the time during which an additional action potential cannot be generated, regardless of the strength of the stimulus.

absolute refractory.

Neurotransmitters can be classified based on their __, effect on the postsynaptic membrane, and their mechanism of action.

chemical structure.

An __ postsynaptic potential (EPSP) is a depolarization that can lead to generating an action potential.

excitatory.

Inhibitory postsynaptic potentials (IPSPs) lead to __ of the neuron, making it less likely to generate an action potential.

hyperpolarization.

After depolarization, the membrane returns to resting potential primarily due to the movement of __ ions out of the cell.

potassium (K+).

It is the __ mechanism that contributes to the resting membrane potential, pushing Na+ and pulling K+ across the membrane.

sodium-potassium pump.

The gap junctions between cells in electrical synapses allow __ current to flow rapidly between adjacent cells.

graded.

Neurotransmitters perform their function by binding to __ on the postsynaptic membrane.

receptors.

The __ of neural pathways includes serial, convergent, divergent, reverberating, and parallel after-discharge circuits.

organization.