How does the root know which way is down?

Plants can feel gravity, the pull that makes things fall. Root cells are made to grow towards that pull, so roots head down into the soil. Shoots do the opposite and grow up, away from the pull and towards the sunlight.

What does it eat when the food packet runs out?

The food packet only has to last until the first leaves open. Then the leaves take over. They catch energy from sunlight and use it to turn water and a gas from the air into sugar. That sugar is the plant's food, so it keeps on growing.

How does a seed grow into a plant?

Roo answers for ages 4–11, then goes 2 steps deeper each time a child asks why.

Roo says

Inside every seed is a tiny baby plant, curled up with a packet of food. When the soil is damp and warm enough, the seed soaks up water and its coat cracks open. A little root pokes out and grows down. Then a shoot pushes up towards the light.

For ages 4–7

Checked against Explainer: How a seed grows into a plant (Science News Explores)
How does the root know which way is down?

Plants can feel gravity, the pull that makes things fall. Root cells are made to grow towards that pull, so roots head down into the soil. Shoots do the opposite and grow up, away from the pull and towards the sunlight.

For ages 6–9

Checked against Explainer: How a seed grows into a plant (Science News Explores)
What does it eat when the food packet runs out?

The food packet only has to last until the first leaves open. Then the leaves take over. They catch energy from sunlight and use it to turn water and a gas from the air into sugar. That sugar is the plant's food, so it keeps on growing.

For ages 8–11

Checked against Explainer: How a seed grows into a plant (Science News Explores)