The Question Below Refers to the Following Information Figure 451
-The Results Most Likely Occurred Because Progesterone Exerts an Experiment

question 6

Multiple Choice

The question below refers to the following information.
In an experiment, rats' ovaries were removed immediately after impregnation and then the rats were divided into two groups. Treatments and results are summarized in the table below
$\begin{array}{lcc}\hline&\text { Group } 1 &\text { Group } 2\\\hline (\text { Daily injections of }&&\\\text { progesterone (milligrams) } & 0.25 & 2.0 \\\text { Percentage of rats that } & & \\\text { carried fetuses to birth } & 0 & 100\\\hline\end{array}$

Figure 45.1
-The results most likely occurred because progesterone exerts an effect on the

• A)general health of the rat.
• B)size of the fetus.
• C)maintenance of the uterus.
• D)gestation period of rats.
• E)number of eggs fertilized.

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Definitions:

Shaping

A method of conditioning by which successive approximations of a desired behavior are reinforced.

Natural Laws

Fundamental principles that govern the natural world, often described through physics and other sciences.

Skinner

B.F. Skinner, an influential American psychologist known for his research in behaviorism and operant conditioning.

Natural Selection

A process by which evolutionary changes occur in a species, where organisms that are better adapted to their environment survive and reproduce more successfully.