What Is a Planetary Nebula

question 63

Multiple Choice

What is a planetary nebula?

• A) The bipolar jets ejected by a T Tauri variable
• B) A planet surrounded by a glowing shell of gas
• C) The disc of gas and dust surrounding a young star that will soon form a solar system
• D) The ejected envelope, often bipolar, of a red giant surrounding a stellar core remnant
• E) A type of young, medium mass star

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Definitions:

Unconditioned Response

An automatic, natural reaction to a stimulus that occurs without prior learning or conditioning.

Salivary Glands

Glands located in the mouth that produce saliva, which aids in digestion and keeps the mouth moist.

Pavlov's Analysis

Pertains to the research and experiments conducted by Ivan Pavlov, especially his work on classical conditioning, demonstrating how dogs could be conditioned to respond to a stimulus that previously had no effect on them.

Unconditioned Stimulus

An Unconditioned Stimulus is a stimulus that naturally and automatically triggers a response without any prior learning or conditioning.