Why Do Leaves Appear in Shades of Yellow,orange,and Red in the Fall

question 130

Multiple Choice

Why do leaves appear in shades of yellow,orange,and red in the fall?

• A) Cooler fall temperatures change the shape of chlorophyll causing it to absorb different wavelengths of light.
• B) The chlorophyll organelles that contain chloroplast pigments breakdown and the leaves reflect more wavelengths of light.
• C) In the fall,chloroplasts begin producing enzymes instead of chlorophyll and these reflect different wavelengths of light.
• D) Other leaf pigments that were masked by the chlorophyll become visible and reflect wavelengths of light other than green.
• E) As the leaves lose chlorophyll,they absorb wavelengths of light that were previously reflected by the pigment.

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Definitions:

Genetic-Programming Theories

Theories that explain biological aging as resulting from a genetically determined developmental timetable.

Immunological Theory

A theory proposing that the immune system plays a significant role in the aging process by becoming less efficient over time.

Wear-And-Tear Theory

A concept suggesting that the body ages as a result of accumulated damage and degradation of cells and tissues over time.

Variable-Rate Theories

Theories that explain biological aging as a result of processes that involve damage to biological systems and that vary from person to person.