Considering the Global Carbon Cycle, Where Are Humans Having a Large

question 20

Multiple Choice

Considering the global carbon cycle, where are humans having a large impact?

• A) terrestrial ecosystems
• B) oceans
• C) atmosphere
• D) beneath the surface of the Earth
• E) Both A and C

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Definitions:

Vascular Cylinder

A central part of the root of plants where xylem and phloem tissues are located, responsible for the transport of water, nutrients, and other substances.

Companion Cells

Specialized cells in the phloem of plants that are closely associated with sieve tube elements and assist with the transport of photosynthetic products.

Pressure Flow Theory

A hypothesis explaining how sugars are moved from the leaves where they're produced to other parts of the plant through phloem.

Parenchyma

In plants, simple tissue composed of living, thin-walled cells; has various specialized functions such as photosynthesis.