A Key Characteristic of Igneous Rocks Is That They ____

question 36

Multiple Choice

A key characteristic of igneous rocks is that they ____.

• A)are the youngest rocks on Earth
• B)are made up of minerals that crystallized from molten rock matter called magma
• C)never contain iron or magnesium
• D)are not as hard as sedimentary rock
• E)always contain more than three different mineral types

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Definitions:

Saprotrophs

Organisms that feed on or derive nourishment from decaying organic matter, playing a vital role in decomposition and nutrient cycling.

Microbial Heterotrophs

Microorganisms that obtain their energy by consuming organic matter, as opposed to producing it themselves.

Pyramids of Numbers

A graphical representation showing the number of organisms at each trophic level in an ecosystem.

Biomass

The total mass of organisms within a given area or ecosystem at a given time, often used as an energy resource.