Interstellar Extinction Is the

question 152

Multiple Choice

Interstellar extinction is the

• A) assimilation of interstellar matter by stars after gravitational attraction and capture.
• B) reduction of the apparent brightness of stars by scattering and absorption of their light by intervening interstellar clouds.
• C) wipeout of species on Earth by intense radiation from a nearby supernova.
• D) deaths of high-mass stars in the space between other long-lived stars.

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Definitions:

Hippocampus

The hippocampus is a brain structure involved in the formation of new memories and is also associated with learning and emotions.

Fornix

A C-shaped structure in the brain, part of the limbic system, that acts as a major output tract of the hippocampus.

Amygdala

A part of the brain involved in processing emotions, including fear and pleasure.

Substantia Nigra

(sub-STAN-sha NI-gra) The structure in the midbrain that controls unconscious motor movements.