Exchange Across a Membrane Requires

question 6

Multiple Choice

Exchange across a membrane requires

• A) moisture only.
• B) transport proteins only.
• C) pressure gradients only.
• D) moisture and pressure gradients only.
• E) moisture, pressure gradients, and transport proteins.

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Definitions:

Constant-Rate

Pertaining to a process or quantity that changes over time at an unvarying speed or amount.

Progressive Tax

A tax system where the tax rate increases as the taxable amount increases, placing a heavier burden on wealthier taxpayers.

Proportional Tax

A taxation system where the tax rate remains constant regardless of the amount subject to tax.

Lump-Sum Tax

A tax of a fixed amount that does not vary with the taxpayer's income or activities.