Virtually All the Carbon- Rich Dust in the Plane of the Galaxy

question 137

Multiple Choice

Virtually all the carbon- rich dust in the plane of the galaxy originated in

• A) planetary nebulae.
• B) white dwarfs.
• C) high- mass stars.
• D) brown dwarfs.
• E) low- mass stars.

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Definitions:

Sensory Neurons

Nerve cells responsible for converting external stimuli from the environment into internal electrical impulses for the brain.

Chemical Messenger

Biologically active molecules such as hormones and neurotransmitters that transmit signals across cells or throughout the body.

Acetylcholine

A neurotransmitter associated with various functions including muscle activation, heart rate, and the modulation of brain activity.

Dopamine

A neurotransmitter involved in many functions, including the reward system, motivation, pleasure, and motor control.