Charles and Francis Darwin Concluded from Their Experiments on Phototropism

question 65

Multiple Choice

Charles and Francis Darwin concluded from their experiments on phototropism by grass seedlings that the part of the seedling that detects the direction of light is the

• A) tip of the coleoptile.
• B) part of the coleoptile that bends during the response.
• C) base of the coleoptile.
• D) cotyledon.
• E) phytochrome in the leaves.

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Definitions:

Troposphere

The lowest layer of Earth's atmosphere, extending from the surface to about 8 to 15 kilometers (5 to 9 miles) high, where nearly all weather occurs.

Acid Rain

Precipitation that has been made acidic by atmospheric pollution, leading to environmental harm, particularly in forests and lakes.

Risk Analysis

The process of identifying, evaluating, and prioritizing risks followed by coordinated efforts to minimize or control their impact.

Ecological Problem

Issues that arise when the natural balance of ecosystems is disturbed, leading to environmental harm and decreased biodiversity.