What Is the Source of Luminosity for Protostars That Have

question 132

Multiple Choice

What is the source of luminosity for protostars that have not yet become hot enough for fusion in their cores?

• A)fusion in their low- density outer layers
• B)light absorbed from nearby stars
• C)energy released by infalling matter
• D)fission from concentrated radioactive elements

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Definitions:

Regenerated

describes something that has been restored or replenished, often relating to natural processes or materials that have been recycled or renewed.

Phagocytosis

The process by which cells engulf and digest foreign particles or microorganisms, an essential part of the immune system.

Pinocytosis

The process whereby a cell engulfs large amounts of liquid.

Active Transport

The movement of molecules across a cell membrane from a region of lower concentration to one of higher concentration, requiring energy.