The Question Below Refers to the Following Information Figure 451
-Melatonin Has Been Found to Participate in All of Experiment

question 17

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
-Melatonin has been found to participate in all of the following except

• A)skin pigmentation.
• B)monitoring day length.
• C)reproduction.
• D)biological rhythms.
• E)calcium deposition in bone.

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Definitions:

Test-tube Method

A technique often associated with laboratory experiments or procedures conducted in vitro, such as the cultivation of microorganisms or cells in a test-tube.

Reproduction

The biological process by which new individual organisms are produced from their parents.

Age Grades

Social categorization based on age, often used in traditional societies to organize individuals into groups with similar responsibilities and rites of passage.

Age Classes

Categories or divisions in a society based on age, used to organize individuals into roles, responsibilities, and social expectations appropriate to their stages in life.