The Two Main Gases Making Up the Lower Atmosphere Are

question 5

Multiple Choice

The two main gases making up the lower atmosphere are

• A)helium and hydrogen.
• B)carbon dioxide and nitrous oxide.
• C)oxygen and methane.
• D)nitrogen and oxygen.
• E)oxygen and carbon dioxide.

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Definitions:

Saprotroph

A saprotroph is an organism that feeds on or derives nourishment from decaying organic matter, essential for nutrient cycling in ecosystems.

Food Chain

A series of organisms each dependent on the next as a source of food, illustrating the flow of energy and nutrients from one organism to another.

Ecological Pyramid

A graphical representation of the relative energy value at each trophic level. See pyramid of biomass and pyramid of energy.

Trophic Levels

The hierarchical levels in an ecosystem, determined by the feeding position of organisms in food chains.