When Charles and Francis Darwin First Documented Phototropism, Why Was

question 29

Multiple Choice

When Charles and Francis Darwin first documented phototropism, why was it important that they germinated the grass seeds in the dark before beginning the experiment?

• A) so the young shoots would be soft enough to bend
• B) so the young shoots would grow slowly
• C) so the young shoots would grow quickly
• D) so the young shoots would grow straight

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Definitions:

Steroids

Organic compounds with four rings arranged in a specific molecular configuration, used in medicine and also known for their performance-enhancing effects in sports.

Set-Point Theory

The theory that the body regulates its weight and energy balance through internal controls, maintaining a stable weight over time.

Basal Metabolism Rates

The rate at which the body uses energy while at rest to maintain vital functions such as breathing and keeping warm.

Dramatic Increases

Significant rises or growth in quantity, size, intensity, or level.