The Reason That Deciduous Leaves Turn Red and Yellow in the Fall

question 18

Multiple Choice

The reason that deciduous leaves turn red and yellow in the fall is

• A)Chlorophyll is converted into bright carotenoid pigments.
• B)When chlorophyll breaks down,the red and yellow pigments which are already present become visible.
• C)It is a chemical reaction involving the formation of ice crystals.
• D)Bright pigments are shifted up from the roots while chlorophyll moves down.
• E)Red and yellow pigments can only be made when temperatures are cool.

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Definitions:

Distal

A term used to describe a location farther from the point of origin or attachment, often used in anatomy to describe the position of body parts.

Negative Feedback

A regulatory mechanism in which a stimulus causes an opposite output in order to maintain an optimal level of whatever is being regulated.

Effector

An organ or cell that acts in response to a stimulus, often referring to muscles or glands responding to neural signals.

Stimulus

A stimulus is any external or internal change that influences the activity of an organism or any of its parts, leading to a physiological response.