Why do leaves change color in Autumn?

Scientific Reasons For Leaves Changing Color

First of all to understand this phenomena one must be familiar with the process called photosynthesis in which plants makes it food. It is a photo chemical reaction

In which the plants absorbs carbon dioxide and water from the surrounding in the presence of sunlight and chlorophyll (which acts as catalyst) and converts them to oxygen and carbohydrates such as sugars and starch.

Red coloration due to Anthocyanins

Now these chlorophyll present inside the chloroplasts of plant are also responsible for giving plants its characteristic green color. Actually there are also other chemical agents which gives other colors to plants but the chlorophyll suppresses them and dominates and we observe green color in these summer and spring seasons. But when autumn comes the nights are long and days short which means less exposure to sun and less production of chlorophyll which results in green color deteriorating and other factors and colors are observed.

Color Influencing Agents

Chlorophyll:

•  These are responsible for giving leaves their green color. It is necessary for photosynthesis, the chemical reaction that enables plants to use sunlight to manufacture carbohydrates for their food.

Carotenoids:

•  These produce yellow, orange, and bright red colors in such things as corn, carrots etc. Foods containing these are really healthy.

Anthocyanins:

•  These gives blue violet or red color to plant.