How do the potatoes underground contain starch?

Potatoes, like many other plants such as corn, rice and wheat, store starch as their primary energy reserve in specialized structures called plastids. In the case of potatoes, the storage plastids are called amyloplasts.

Potatoes develop tubers, which are modified underground stems. These tubers are where the starch is stored to sustain the plant during dormancy and provide nutrients for new growth.

The process of starch synthesis in potato tubers begins with photosynthesis in the leaves. During photosynthesis, plants convert carbon dioxide (CO2) from the atmosphere and water into glucose, a simple sugar, using energy from the sun.

The glucose is then transported from the leaves to the tubers, where it is converted into starch. The conversion process involves several enzymatic reactions that result in the formation of long chains of glucose molecules, known as amylose and amylopectin, which make up the starch.

The starch granules are stored within the amyloplasts, which are abundant in the tuber cells. These granules can be observed under a microscope as small, round or oval structures. When you cut open a potato, you can see the starch in the form of white granules dispersed within the tuber's flesh.

The starch content of potatoes varies depending on the variety and growing conditions. Some potato varieties are known to have higher starch content than others. Factors such as temperature, light, and water availability during the growing season can also influence the starch content.

Starch serves as a valuable source of energy for humans and animals, making potatoes an important staple food worldwide. It is used in a variety of culinary preparations, including mashed potatoes, french fries, chips, and many other dishes.