AP BIOLOGY

Detailed explanation-1: -As night length increases in the autumn, chlorophyll production slows down and then stops and eventually all the chlorophyll is destroyed. The carotenoids and anthocyanin that are present in the leaf are then unmasked and show their colors.

Detailed explanation-2: -The chlorophyll breaks down and the green fades away, letting the yellow/orange carotenoids blaze forth, giving autumn its splash, dash and panache. At the same time, other chemical changes occur, giving rise to more pigments which vary from yellow to red to blue.

Detailed explanation-3: -As the season changes, temperatures drop and days get shorter. Trees get less direct sunlight, and the chlorophyll in the leaves breaks down. The lack of chlorophyll reveals yellow and orange pigments that were already in the leaves but masked during the warmer months.

Detailed explanation-4: -Photosynthesis, or the production of sugars that depend on sunlight, begins to slow down in response to the change in the amount of light. This leads to a reduction of chlorophyll, the pigment that supports photosynthesis and gives leaves their green color.

Detailed explanation-5: -Leaves tend to change faster north-to-south and in higher elevations first. Low temperatures above freezing will favor producing bright reds in maples. However, early frost will weaken the brilliant red color. Rainy and/or overcast days tend to increase the intensity of fall colors.