A Planetary Nebula Is a

question 116

Multiple Choice

A planetary nebula is a

• A) cloud of gas surrounding a very young star in which planets are expected to form.
• B) spherical, rapidly expanding cloud of gas produced by a supernova explosion.
• C) gas cloud surrounding a planet after its formation.
• D) shell of gases ejected from the surface of red giant star.

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Definitions:

Middle Ear

Portion of the ear consisting of the tympanic membrane, the oval and round windows, and the ossicles, where sound is amplified.

Semicircular Canals

Structures in the inner ear involved in maintaining balance.

Vertigo

Equilibrium disorder that is often associated with problems in the receptors of the semicircular canals in the ear.

Tympanic Membrane

Membranous region that receives air vibrations in an auditory organ; in humans, the eardrum.