Amyloplast facts for kids

An amyloplast is a tiny part inside a plant cell that works like a storage pantry for starch. You can find these special storage units in plants that are rich in starch, like tubers (think potatoes!) and many fruits.

What is an Amyloplast?

An amyloplast is a special kind of organelle found only in plant cells. Think of organelles as the "mini-organs" of a cell, each with a specific job. The main job of an amyloplast is to make and store starch. Starch is a type of carbohydrate that plants use for energy.

Where are Amyloplasts Found?

Amyloplasts are common in parts of plants that need to store a lot of energy. You'll find them in:

• Roots: Like in carrots or sweet potatoes.
• Tubers: Such as potatoes, which are underground stems packed with starch.
• Seeds: For example, in corn, rice, or wheat grains, where starch provides energy for the new plant to grow.
• Fruits: Some fruits store starch, which often turns into sugar as the fruit ripens.

What Do Amyloplasts Do?

The main role of amyloplasts is to store starch. Plants make their own food using sunlight through a process called photosynthesis. This food is usually a sugar called glucose. When a plant makes more glucose than it needs right away, it converts the extra glucose into starch. Starch is a great way to store energy because it's compact and easy for the plant to break down later when it needs energy, like during the night or when it's growing new parts.

Starch Storage

Inside an amyloplast, starch is stored in special structures called starch grains or starch granules. These granules can be different shapes and sizes depending on the type of plant. When the plant needs energy, enzymes inside the amyloplast can break down the starch back into sugar, which the plant then uses to fuel its growth and daily activities.

Gravity Sensing

In some plant cells, especially in roots, amyloplasts have another important job: helping the plant know which way is up and down. These special amyloplasts are called statoliths. They are heavier than other parts of the cell and settle at the bottom due to gravity. This movement signals to the plant's cells which direction to grow, ensuring roots grow downwards into the soil and shoots grow upwards towards the light.

Amyloplasts vs. Other Plastids

Amyloplasts belong to a family of organelles called plastids. Plastids are like a group of specialized factories in plant cells, and each type has a different job.

• Chloroplasts: These are the most famous plastids. They contain chlorophyll and are responsible for photosynthesis, turning sunlight into energy. Chloroplasts are usually found in the green parts of plants, like leaves.
• Chromoplasts: These plastids contain colorful pigments (not chlorophyll) and give fruits, flowers, and some roots their vibrant colors (like the red in a tomato or the yellow in a daffodil).
• Leucoplasts: Amyloplasts are actually a type of leucoplast. Leucoplasts are colorless plastids that are mainly involved in storing things like starch, oils, or proteins. Amyloplasts are the ones specifically for starch.

So, while chloroplasts are busy making food, amyloplasts are busy storing it for later!

See also

In Spanish: Amiloplasto para niños