You May Have Observed Plants Rotate Towards a Light Source

question 46

Multiple Choice

You may have observed plants rotate towards a light source, thereby increasing the plant's ability to intercept light energy and increase photosynthesis. You, however, are given the task of preventing grass seedlings from rotating toward the light. Using your knowledge of phototropism, which of the following experimental procedures would you use to complete your task?

• A) Cover the growing tip of the grass seedling with black paper.
• B) Supply the seedlings with very dim light (red light does not induce a bend).
• C) Cover the portion of the seedling below the tip with a black shield.
• D) Supply the seedling with nutrient-rich fertiliser solution.

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Definitions:

Basal Ganglia

A group of nuclei in the brain involved in coordinating movement, as well as aspects of learning and emotion.

Flexor Muscles

Muscles that decrease the angle between bones on two sides of a joint, involved in bending or flexing parts of the body.

Trunk

The main part of the body, excluding the head, neck, and limbs, housing the majority of vital organs.