Autumn leaf

by Patricia Dennis

Title

Autumn leaf

Artist

Patricia Dennis

Medium

Photograph - Digital

Description

A cluster of zinfandel grapes peek from behind a cloak of fall colors. Taken in the Napa Valley, California.
What causes the color? Carotenoids are present in leaves the whole year round, but their orange-yellow colors are usually masked by green chlorophyll. As autumn approaches, certain influences both inside and outside the plant cause the chlorophylls to be replaced at a slower rate than they are being used up. During this period, with the total supply of chlorophylls gradually dwindling, the "masking" effect slowly fades away. Then other pigments that have been present (along with the chlorophylls) in the cells all during the leaf's life begin to show through. These carotenoids provide colorations of yellow, brown, orange, and the many hues in between.
The carotenoids occur, along with the chlorophyll pigments, in tiny structures called plastids within the cells of leaves. Sometimes they are in such abundance in the leaf that they give a plant a yellow-green color, even during the summer. Usually, however, they become prominent for the first time in autumn, when the leaves begin to lose their chlorophyll.

Uploaded

October 10th, 2013

Statistics

Viewed 496 Times  -  Last Visitor from Cambridge, MA on 04/20/2024 at 5:02 AM

Colors

Embed

Share

Sales Sheet

Tags