A Frog Can Absorb Oxygen Through Its Skin and Lungs

question 83

Multiple Choice

A frog can absorb oxygen through its skin and lungs.Which is an advantage of absorbing oxygen through the lungs?

• A) The heart pumps oxygen from the lungs into the bloodstream.
• B) Oxygen absorbed in the lungs enters the blood stream.
• C) Air in the lungs has a higher concentration of oxygen than air in the atmosphere.
• D) Oxygen diffuses across cells more slowly than across the lining of the lungs.
• E) Lungs have more surface area than the skin.

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Definitions:

Nonexperimental Method

A research method where the researcher observes and records behavior without manipulating any variables.

Experimental Control

The process of keeping variables constant or regulating external factors to ensure that observed effects are due to manipulated variables only.

Independent Variable

A manipulated factor in an experiment, chosen to determine its potential effect on a dependent outcome.

Dependent Variable

The outcome factor in a study that changes in response to manipulations of the independent variable.