Evidence for Phototropism Due to the Asymmetric Distribution of Auxin

question 104

Multiple Choice

Evidence for phototropism due to the asymmetric distribution of auxin moving down the stem

• A) was first demonstrated in the coleoptiles of monocots.
• B) has been found in all monocots and most eudicots.
• C) has been shown to involve only IAA stimulation of cell elongation on the dark side of the stem.
• D) can be demonstrated with unilateral red light, but not blue light.
• E) is now thought by most plant scientists not to involve the shoot tip.

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Definitions:

Additive

A substance added to another substance to alter or improve its qualities, such as food additives to enhance flavor or preserve freshness.

Dichromatic

Having two colors; in vision science, it refers to a form of color blindness in which a person can distinguish only two of the three basic color channels.

Subtractive Color Mixing

A process by which colors are created by absorbing or filtering out parts of the light spectrum, as seen in mixing pigments in paints.

Blending

The cognitive process of combining two or more distinct entities or ideas into a new, unified concept.