Sometimes We Cannot Manipulate Some of the Variables We Are

question 53

Multiple Choice

Sometimes we cannot manipulate some of the variables we are most interested in (e.g.,having cancer) .We use naturally occurring groups.This form of research is known as:

• A)correlational
• B)quasi-experimental
• C)clinical trials
• D)controlled trials

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Definitions:

Major Function

The primary role or purpose that something serves or is designed to perform.

Stomata

Tiny openings or pores in plant tissue that allow for gas exchange, including the intake of carbon dioxide and release of oxygen.

Membrane Permeability

The ability of a membrane to allow substances to pass through it, which can be regulated to maintain cellular homeostasis.

Acid Precipitation

Precipitation that is acidic as a result of both sulfur and nitrogen oxides forming acids when they react with water in the atmosphere.