From the brains behind brains on, this is the moment of um.

Answering those questions that make you go, um, um, um, moment of um, to you from APM Studios, I'm Tommy the tomato plant.

Yeah, remember me? I'm the little tomato plant your dad bought from the hardware store two months ago and plunked in

a pot of dirt. I remember that day like it was yesterday. The sun was shining, the birds were

singing, and I thought to myself, Tommy, today's the first day of the rest of your life. You're

finally going home and you're going to grow delicious cherry tomatoes. But guess what? No one remembered to water me.

I'd been living on your patio in the beating sun without so much as a drop to drink. Do you know how

hard it is to produce high-quality super sweet cherry tomatoes without water? Look at these little shriveled up

things.

They don't even look like tomatoes.

If only I could get a sip of water,

I'd suck it all up to my roots and be a brand new plant.

I don't know how it works.

It just works.

My buddy Sebastian wanted to know too.

How do plant roots suck up water?

The simplest way to describe it is like a straw. My name is Brandy Cannon Horse, and I am a PhD

student at Stanford University. I study science education and I study plant.

It's sort of a transportation tissue, so it allows for water to be sucked straight up.

Water is actually really attracted to itself.

So when one water molecule is being pulled up, they kind of hold hands and they create a chain

of water molecules that are pulled all the way up through the straw and through to the leaves.

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