Over the Course of One Night, an Observer at Any

question 254

Multiple Choice

Over the course of one night, an observer at any given location on Earth sees the constellations gradually shift across the sky from east to west. This is caused primarily by the

• A) inherent rotation of the universe.
• B) rotation of Earth around its own axis.
• C) precession of the spin axis of Earth.
• D) orbital motion of Earth around the Sun.

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Definitions:

Dura Mater

The outermost, thick, and durable membrane of the three layers of the meninges that envelop the brain and spinal cord, providing protection.

Sciatic Nerve

A large nerve that runs from the lower back down the back of each leg, involved in controlling the muscles of the back of the knee and lower leg.

Spinal Cord

A major part of the central nervous system that extends from the base of the skull to the lower back and is responsible for transmitting nerve signals between the brain and the body.

White; Gray

Refers to the two types of matter in the central nervous system; white matter consists of myelinated axons, while gray matter contains neuron cell bodies.