warning

Content guidance

Risk assessment required - equipment

Adult supervision required

video

Lesson video

In progress...

Loading...

Hello, my name is Ms. Mehrin, and I'm really excited to be learning all about the function of roots with you.

Let's begin.

Welcome to today's lesson from the unit, "What Plants Do and What They Need." Your learning outcome is: I can describe why plants have roots.

Now I know that learning can sometimes be a little bit challenging, but that's okay because it just means that we are going to learn lots of fabulous new things together.

Now here are your key words for today's lesson.

Now you'll notice that the definitions are also here, and I will be going through these throughout today's lesson.

However, if you find it helpful, you can pause the video here and you can jot these down.

Fantastic.

Well done.

So our lesson is split into two parts today.

Let's begin with the first part, roots.

Andeep has been learning about the parts of a plant, and he says, "I know that most plants have leaves and stems, and many plants have flowers.

Are there any other plants? Are there any other parts that most plants have?" What do you think? I'll give you five seconds to think about your answer.

Off you go.

Fantastic.

Well done.

So most plants have roots, and these are the plant roots in soil.

And roots are found at the bottom of the plant, and they usually sit below the surface of the soil so we can't always see them.

Now where do the roots of a plant usually grow? Is it A, at the top of the plant, B, around the stem of the plant, or C, at the bottom of the plant below the surface of the soil? I'll give you five seconds to think about your answer.

Off you go.

Fantastic.

Well done, it's C.

Now the function of something is its task or job.

So the function of leaves is to make food for the plant.

Now, what do you think is the function of roots? I'll give you five seconds to think about your answer.

Off you go.

Fantastic.

Well done.

Now roots have two main functions.

So they provide support for the plant, holding it firmly in the ground.

And we sometimes call this anchoring the plant because the roots act like an anchor holding it in place.

Now roots are especially useful in windy conditions as they stop the plant from blowing over.

So here we can see these trees and are being blown by the wind.

But they're not falling over, and that's because the roots are anchored into the ground, keeping that tree in place.

Now another function of roots is absorbing water and nutrients from the soil so the plant can grow and be healthy.

Now let's do a quick check-in of your learning so far.

What are the functions of roots? Is it A, attracting insects to the plant, B, taking in water and nutrients for the plant, C, making food for the plant, or D, anchoring the plant in the soil? I'll give you five seconds to think about your answer.

Off you go.

Fabulous.

Well done.

The answer is B and D, taking in water nutrients for the plant and anchoring the plant in the soil.

Now here is your first task for today.

It says, "Closely observe some different types of roots in real life or observe the photographs of roots on the next slides." So I'll show you those in a second.

Now, you could use hand lenses or microscopes to get a close look at the roots, and I want you to make notes to describe what you see.

So let's have a look.

So here we have two pictures.

So you can either use these or you can use real life plants and use hand lens or a microscope to do your observations.

And here are two more as well.

And here is the fifth one.

So what I'd like you to do now is to pause the video here and have a go at doing this activity.

Off you go.

Fabulous.

Well done.

Well done.

So all of the different types of roots were long, and most of them were also thin.

The carrot roots were thicker, but I could also see small thin roots branching off.

Apart from the carrots, the roots were all white or very pale yellow.

They all had lots of tiny hairs on them.

Some of the hairs were difficult to see without a microscope.

Now are your observations similar to Alex's or are they different? Okay, so now we are on to the second part of our learning, which is how roots take in water and nutrients.

So Sam has been learning about the function of plant roots, and she says, "How do the roots take in water and nutrients? Do they suck water up like a straw?" What do you think? I'll give you five seconds to think about your answer.

Off you go.

Fabulous.

Well done.

So roots don't suck water up like a straw.

And we can see some roots here in this glass.

So it's really easy to see them.

What they do is they absorb the water and the nutrients through their surface.

And absorbing means when you soak something up, so soaking things up.

Now you can see how absorbing works by dipping a paper towel into some water.

So you can see here that the paper towel is absorbing the water, it's soaking the water up.

Now a straw can only suck things up from the end, which is different to roots.

The whole root can absorb water and nutrients, not just the end, just like the paper towel.

Now many roots are covered in tiny hairs that can also absorb water and nutrients from the soil.

So you can see this really well if you have a microscope or a good hand lens as well.

And if you go and have a look at the roots that you were observing before, you'll be able to see, you might be able to see some of these tiny hairs, and they can absorb the water and the nutrients from the soil as well.

Now have a really good thing.

Did you notice any of those tiny hairs when you were observing the roots? And if not, you can always pause the video here and you can go back and see if you can notice any on your plant.

So I'll give you five seconds, or if you need to, you can pause the video here.

Off you go.

Fantastic.

Well done.

So Sam makes a model to help explain how roots absorb water and nutrients.

So what she does is she cuts long thin shapes from some kitchen roll to represent the roots.

And the reason why Sam is using kitchen roll is kitchen roll is fantastic for absorbing liquids, which is often why you would, you will find it in the kitchen.

You'll find kitchen roll in the kitchen because if you have a spill or something like that, you can use it to quickly mop up any spills because it absorbs water and liquids so well.

So kitchen roll is designed to do that.

So it's a fantastic way of using it to represent roots as well.

She adds food colouring to some water to represent the water and the nutrients, just like in this picture here.

And then she dips her roots into the water and nutrients, and she can see how they are absorbed.

So if you look really closely at this picture and you observe it, you can see all of that wonderful water and all of those wonderful nutrients being soaked right up by that paper towel, which represents the way that roots soak up that water and those nutrients from the soil.

Now let's do a quick check-in of your learning.

True or false? Roots suck up water and nutrients from the soil.

Is that true or false? I'll give you five seconds to think about your answer.

Off you go.

Fantastic.

The answer is false.

Now let's see if you can justify your answer.

Is it because, A, roots only suck up water from the soil, not nutrients, or B, roots absorb water and nutrients rather than sucking it up? Again, I'll give you five seconds to think about your answer.

Off you go.

Fabulous, the answer is B, roots absorb water and nutrients rather than sucking it up.

So now we are on to task B, and it says, "Think about Sam's model." I want you to explain how Sam's model is similar to real roots.

So what do you know about kitchen towels, and what do you know about roots? Why do you think Sam has used the kitchen towel? So I want you to explain how the model is similar to real roots.

Then I want you to explain how the model is different to real roots.

So why is the paper towel different to actually having real roots? Think about what you know, go back, and look at the roots that are in front of you as well.

Have a go at doing Sam's model if that's going to help you.

And this will make it much easier for you to do this activity.

So I'd like you to pause the video here and have a go at doing that.

Off you go.

Fabulous.

Well done.

So Sam's model roots absorb water just like real roots, and her kitchen towel was shaped like real roots as well.

However, the differences are that real plant roots would normally be in soil, not just water.

We can't really see the nutrients in soil like we can see the food colouring.

And Sam's model doesn't have root hairs like real roots.

Now we are onto the summary of our learning today.

The roots of a plant usually sit below the surface of the soil, and they have two main functions.

One is to provide support for the plant by holding the plant upright.

So that was called anchoring the plant.

And number two, to absorb water and nutrients from soil to provide the plant with what it needs to grow and stay healthy.

I'm really proud of your fantastic work today.

You've worked brilliantly, brilliantly, and you've used your observation skills really well.

So well done.