In the Fall, the Leaves of Some Trees Change Color

question 19

Multiple Choice

In the fall, the leaves of some trees change color. This happens because chlorophyll breaks down and the accessory pigments become visible. What hormone triggers this response in plants?

• A) phototropin
• B) abscisic acid
• C) cytokinin
• D) ethylene

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Definitions:

Standard Deviations

An indicator of how much the values in a collection differ from each other.

Probability Density Functions

Mathematical functions that describe the likelihood of a continuous random variable taking on a particular value.

Continuous Random Variables

Variables capable of assuming countless values within a specified range.

Normal Probability Distribution

A continuous probability distribution characterized by a symmetrical bell-shaped curve, where the mean, median, and mode are all equal.