A Cardiovascular System Is Not Necessary in the Hydra Because

question 34

Multiple Choice

A cardiovascular system is not necessary in the hydra because the hydra

• A) is an aquatic animal.
• B) has no skeleton.
• C) is only two cells thick.
• D) has tentacles to move water.
• E) does not move rapidly.

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Definitions:

Control Group

In experimental research, the group of subjects that does not receive the experimental treatment, serving as a baseline for comparison.

Independent Variable

A variable in research that is manipulated or changed to observe its effect on a dependent variable.

Low-Fat Diet

A dietary approach that aims to reduce the intake of fatty foods, especially saturated fats and cholesterol, for health reasons.

Aggressive Behavior

Actions or attitudes that aim to harm or intimidate another person, stemming from a variety of psychological, environmental, or biological factors.