When Many of the Atoms or Molecules in a Sample

question 103

Multiple Choice

When many of the atoms or molecules in a sample have been excited into a metastable state, a(n) ______________ has occurred.

• A) ultraviolet catastrophe
• B) population inversion
• C) coherent emission
• D) incoherent absorption

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Definitions:

Chlorophyll

The green pigment found in the chloroplasts of plants, algae, and some bacteria, essential for photosynthesis.

Reflect

The act of light, sound, or heat waves being thrown back from a surface without being absorbed.

Stroma

A fluid space of the chloroplast, enclosed by the chloroplast inner membrane and surrounding the thylakoids; site of the reactions of the Calvin cycle.

Chloroplast

An organelle found in plant cells and some microorganisms that is the site of photosynthesis.