Visible Radiation May Be Useful for Transmitting

question 21

Multiple Choice

Visible radiation may be useful for transmitting

• A) signals over wide areas towards a number of nearby stars
• B) signals to advanced civilizations that never develop radio astronomy
• C) focused signals to individual star systems nearby
• D) signals to civilizations in neighboring galaxies

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Definitions:

Spatial Summation

The process by which multiple synaptic inputs from different locations on the same neuron combine to influence the firing rate or activity of the neuron.

Dendrites

The branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body.

Back Propagation

Reverse movement of an action potential into the soma and dendritic field of a neuron; postulated to play a role in plastic changes that underlie learning.

Action Potential

A temporary reversal of an electric polarization of the membrane of a nerve cell or muscle cell, allowing for the transmission of signals.