How Plants Grow

A free interactive lesson on how plants grow — from seed to full plant. Learn how photosynthesis works, what roots, stems and leaves do, and why plants need sunlight and water. Based on Class 4 Science. Includes a quick quiz.

Class 4 ScienceClass 4 / Grade 4Ages 6–9
Lesson
🌿 How Plants Grow
A tiny seed grows into a mighty tree!Undergroundseedtiny root🌿 leavesmake foodtall tree!Water + Sunlight + Soil = a living plant

A single tiny seed, no bigger than your fingernail, can grow into a tree taller than a house. How? The seed contains a baby plant and a small food store to get it started. Once it sprouts, the plant builds everything it needs from just three things — sunlight, water, and air.

How do plants make food?

Plants make their own food through photosynthesis. They take in sunlight through their leaves, absorb water through their roots, and take in carbon dioxide through tiny pores called stomata. Using sunlight as energy, they combine water and carbon dioxide to make glucose — their food — and release oxygen as a byproduct. This oxygen is what we breathe.

What do roots, stems and leaves do?

Roots anchor the plant in soil and absorb water and minerals.

Stems carry water and nutrients up to the leaves and support the plant structure.

Leaves are the food factories — they contain chlorophyll, the green pigment that captures sunlight.

Frequently asked questions

What is photosynthesis?

Photosynthesis is the process by which plants use sunlight, water and carbon dioxide to make glucose (their food) and release oxygen.

Why are leaves green?

Leaves are green because they contain chlorophyll — a pigment that absorbs red and blue light and reflects green light.

What do roots do?

Roots anchor the plant in soil and absorb water and minerals needed for photosynthesis and growth.

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