Which Is Not an Adaptation Seen in Fish Gills

question 50

Multiple Choice

Which is not an adaptation seen in fish gills?

• A) A countercurrent exchange system
• B) Bidirectional ventilation of the gills
• C) Morphological features that increase the surface area available for gas exchange
• D) Morphological features that decrease the path length for diffusion of the respiratory gases
• E) Morphological features that maximize the efficiency of O₂ extraction

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Definitions:

R-Squared

A statistical measure that represents the proportion of the variance for a dependent variable that's explained by an independent variable or variables in a regression model.

Dependent Variable

A variable in an experiment or study whose changes depend on the manipulation of one or more independent variables.

Independent Variable

An independent variable is a condition or factor that can be manipulated in an experiment to determine its effect on a dependent variable, establishing cause-and-effect relationships.

Break-Even Analysis

A financial calculation to determine the volume of production or sales at which total revenues will equal total costs.