Refer to the Figure

question 19

Multiple Choice

Refer to the figure.
These results, showing the change in testis length in male red crossbills over time, support the hypothesis that crossbills

• A) are reproductively opportunistic birds that maintain full reproductive capacity throughout the year.
• B) have an underlying reproductive cycle that is dependent on photoperiod.
• C) only use seed abundance, an unpredictable environmental cue, to determine reproductive capacity.
• D) do not rely on environmental cues to entrain their reproductive cycle.

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Definitions:

Slavery

A system in which individuals are owned by others, deprived of personal freedom, and compelled to perform labor or services without the right to compensation.

Raising Money

The act of collecting or acquiring funds for a specific purpose, such as for a business venture, charitable cause, or project.

War Bonds

Securities issued by a government to finance military operations during times of war, encouraging citizens to lend money with the promise of repayment with interest.

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Military leaders who commanded the Union armies during the American Civil War, fighting against the Confederate states.