How do roots sense where gravity is pulling?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. How do roots sense where gravity is pulling?

The Big Idea

Plant a seed upside down, and the root still grows down! How does it know which way is down? Roots can sense gravity!

Heavy Grains

Step one: Heavy Grains. In the tip of each root are tiny, heavy grains called statoliths. They settle to the low side of the cells.

Bending Down

Step two: Bending Down. The settled grains tell the root which way is down. Then the root bends that way.

Shoots Go Up

Step three: Shoots Go Up. Shoots do the opposite and bend upward. On the space station, where gravity feels very weak, plants use light as a guide instead.

A Closer Look

Let's take a closer look! Gravity pulls down. Statoliths settle low. The root tip notices. The root bends down.

Quick Facts

Quick facts! Astronauts have grown plants in space to learn how roots behave without gravity. Turn a seedling on its side, and its root will bend back down. Statoliths are tiny starch grains inside special cells. Shoots grow up, toward the light.

Think Like a Scientist

Now, think like a scientist! Put a bean seed on a damp paper towel inside a clear bag. Tape the bag to a window, out of direct sun. When the root sprouts, turn the bag sideways. Watch the root bend downward over a few days. Draw what happens each day.

Outro

Roots sense gravity with tiny, heavy grains called statoliths that settle to the low side of cells, telling the root which way is down so it can bend that way. Science is amazing! Keep wondering and keep exploring! Share what you learned with someone at home, and see what they think! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!