In the Edge-On Sketch of a Spiral Galaxy, Pick the Letter

question 49

Multiple Choice

In the edge-on sketch of a spiral galaxy, pick the letter corresponding most nearly to the location of globular clusters.

• A)A
• B)B
• C)C

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Definitions:

RAS

Acronym for the Reticular Activating System, a network of neurons located in the brainstem that regulates wakefulness and sleep-wake transitions.

Sleep-Wake Cycle

The circadian rhythm that regulates periods of sleepiness and wakefulness throughout a 24-hour period.

Narcolepsy

A rare condition with symptoms that can include sleep paralysis and cataplexy.

Insomnia

A sleep disorder characterized by trouble falling asleep, staying asleep, or experiencing restorative sleep, leading to daytime dysfunction.