Plants manufacture starch through a process called photosynthesis, which involves the conversion of light energy from the sun into chemical energy stored in the bonds of molecules. The primary source of energy for photosynthesis is sunlight, which is absorbed by pigments called chlorophyll found in the chloroplasts of plant cells.
The process of photosynthesis can be described by the following equation:
6 CO2 + 6 H2O + light energy -> C6H12O6 + 6 O2
This equation represents the conversion of carbon dioxide and water into glucose, a simple sugar, and oxygen, which is released into the atmosphere as a byproduct. The light energy is used to drive the chemical reactions that convert the CO2 and H2O into glucose.
During photosynthesis, the carbon dioxide is taken in through small pores on the surface of the leaves called stomata. The water is absorbed by the roots and transported up through the plant to the leaves. Inside the chloroplasts, the CO2 and H2O are combined through a series of chemical reactions to produce glucose and oxygen.
The glucose produced during photosynthesis is used by the plant as an energy source, but it can also be converted into other forms of energy storage, such as starch. Starch is a complex carbohydrate made up of long chains of glucose molecules. It is stored in the plant's cells, usually in the form of granules, and is used as a source of energy when the plant needs it, such as during periods of darkness or when the plant is under stress.
In summary, plants manufacture starch through the process of photosynthesis, which involves the conversion of light energy from the sun, CO2, and H2O into glucose and oxygen. The glucose is then converted into starch, which is used as a source of energy storage for the plant.