How Does Carbon Dioxide Enter a Leaf

question 31

Multiple Choice

How does carbon dioxide enter a leaf?

• A) Atmospheric pressure forces CO₂ through pits on the leaf surface.
• B) Dissolved CO₂ is transported from roots to leaves in the xylem.
• C) CO₂ diffuses through the epidermis into the mesophyll.
• D) CO₂ is moved by active transport into the leaf by special cells called guard cells.
• E) CO₂ passes through openings called stomata on the leaf surface.

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Definitions:

Hourly Fee

A billing method where a service provider charges based on the number of hours worked.

Flat Fee

A charged price for a service that does not vary with usage or time.

Overhead

All manufacturing costs that cannot be directly traced to a product. Overhead includes indirect labor and materials, plant depreciation, insurance and property taxes, plant management salaries, and so forth. See Indirect Cost Pool.

Direct Labor

The workforce involved in the hands-on manufacturing of goods or provision of services.