ShmoopTube

00:13

Meet Joe.

00:14

This is Joe after a long winter of hibernation. [Joe with his hands on a window looking outside]

00:18

He's can't wait to experience the warmth of spring and summer again! [Joe looks excited as the sun comes out]

00:21

And here's Joe after his very first day at the beach. [Joe sunbathing]

00:24

Huh.

00:25

We haven't seen something that red since we ate at Red Lobster last week… [Joe is sunburnt]

00:29

So why does Joe look like something we'd eat with cheddar bay biscuits?

00:33

Bingo.

00:33

The sun.

00:35

The sun produces sunlight, shocking, we know, and it can have an effect on lots of different [Coop pointing at a blackboard]

00:40

things –one of those things being the pigment of a plant.

00:43

But plants aren't exactly going to the salon to work on their tans. [Plants walking to 'Plant Bronze World']

00:47

So what causes them to have different pigments? [Plant on a sunbed]

00:49

Well, it all depends on where they're growing.

00:51

For example, a plant growing out in the middle of a field all by itself, is going to have

00:55

a lot more direct exposure to the sun than one that that grows on the floor of a dense jungle. [Plant surrounded by tall trees]

01:00

And so, just like how we wear sunscreen and hats when we go out into the sun—well, most [People wearing their hats and sunglasses]

01:05

of us, anyway, Joe—these different plants adapt themselves to their situations. [Joe jumps into a hole in the ground]

01:10

An essential job of a plant is to absorb sunlight to be used in the photosynthesis process! [Plant vacuuming up sunlight]

01:15

In order to do this, plants have a variety of different pigments.

01:18

Pigments help the plant suck up as much of that good ol' sunlight as possible.

01:22

One such pigment is called chlorophyll a, which is found in all plants, no matter where they live. [Dino pointing at a blackboard]

01:28

But depending on their location and exposure to sun, plants might also have other pigments,

01:33

including chlorophyll b, chlorophyll c, and b-carotene.

01:37

Each of these pigments can affect the appearance of the plant itself.

01:40

For instance, chlorophylls are especially green in color when extracted, [Plant turns green]

01:45

while carotenes are orange. [Plant turns orange]

01:46

You know, like carrots?

01:48

Carrots…carot-ene eh, eh? [Carrot appears]

01:52

Well, most of them anyway.

01:54

Some plants even have pigments that protect against UV light – exactly like sunscreen [Plant holding a bottle of sunscreen]

01:58

does, Joe.

01:59

But it all comes down to what each particular plant needs based on its location and access to the sun.

02:05

And unlike some of us, plants tend to know exactly how much sun protection they really [Plant sunbathing]

02:09

need…Joe.

02:11

Now if you'd excuse us, we need to whip up a batch of cheddar bay biscuits.

Full Transcript