Use the Accompanying Figure to Answer the Following Question

question 20

Multiple Choice

Use the accompanying figure to answer the following question
-Second- growth forests _______________

• A)are those forests in the National Parks that are protected from logging
• B)are less abundant on Earth today than they were 500 years ago
• C)are forests whose timber has second- rate value
• D)are forests that establish themselves after virgin timber has been removed from an area
• E)in North America are mostly in British Columbia and Alaska

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Definitions:

Base

A substance that can accept hydrogen ions (protons) or more generally, donate a pair of valence electrons; in nucleic acids, a nitrogen-containing molecule that forms part of the genetic code.

Denitrifying Bacteria

Bacteria involved in the nitrogen cycle, converting nitrates in soil into nitrogen gas, thereby reducing nitrogen availability to plants.

Nitrate

A polyatomic ion with the chemical formula NO3− or a compound containing this ion; important in the nitrogen cycle and used in fertilizers.

Nitrogen Gas

A diatomic, colorless, odorless, and tasteless gas that makes up about 78% of the Earth's atmosphere.