Hello there.

My name is Mr. Wilshire.

And in this lesson, we're going to be looking at how water is transported in plants.

The outcome for this lesson is I can investigate the way in which water is transported in plants.

There are some keywords for us to remember as we work our way through this lesson.

The first is roots.

Then, it's stem.

Next up, absorb.

After that, transport.

And finally, observe.

Don't worry if you're not too sure what some of these words mean, because the definitions have appeared on the screen for you now.

So you can have a look over it, remind yourself, and restart the video when you're ready to continue.

The first part of this lesson is called the function of the stem.

Most plants have roots, leaves, and a stem.

Here, you can see a selection of different types of plant.

Many plants also produce flowers at certain times of the year.

You can see there, in the middle, there's two examples of flowers.

There's also an example of flowers on the end there, but they're on a tree, so that's known as blossom, isn't it? And the very first picture there is a tree that seems to be growing off the edge of a cliff, so you can see all of the roots.

Plant stems can be different shapes and sizes.

There's a flower in the first picture there.

It looks like a bit of bamboo growing up the side there.

And in the third picture, there's another stem with lots of little shoots of flowers coming off of it.

But the fourth one, that doesn't look like a stem at all, does it? Ah, that's because the stems of trees are often called trunks.

These stems can get very, very big.

They support the rest of the tree, the branches, the leaves, the blossom, anything else that grows on it, and they also support lots of life as well.

So even though we might call it a trunk on a tree, it's actually known as the stem.

The functions of roots are to anchor the plant and absorb nutrients and water from the soil.

So if the roots aren't very strong, the plant has a strong likelihood of being blown over.

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

The leaves usually angle their way to collecting sunlight as it shines down from up above.

They'll help to move the plant over time to try and make sure it gets the most sunlight possible across the day.

Do you know what the function of the stem is though? So the roots, they create the anchor.

They support everything.

The leaves, they collect the sunlight as well.

The flowers, they attract lots of different pollinators in.

But what does the stem do? Is it just to support the rest of the plant? You decide.

Have a discussion.

What's the function of the stem? Well, what did you decide? Is the stem an important and integral part of the plant as well? Does it have a separate function from everything else? Or is it just there to look pretty? The stem provides support for the plant.

It holds the leaves and the flowers above the ground.

If it grew along the bottom of the ground, it would be very easy for other animals to eat it or even for it to get trampled.

So the stem is there to make sure that it goes upright.

Plant stems also play a part in transporting water and nutrients around the plant.

Of course, yes, the stem goes from the top to the bottom, or the bottom to the very top, depending on how you look at it.

It's there to connect up to the roots, then it connects to the leaves, then it connects to the flowers and every other part of the plant as well.

So it's able to transport water all around the plant, and that is essential for life and growth.

Stop and think.

Which of these are functions of the stem? Is it making food for the plant? Is it providing support for the plant? Is it transporting water and nutrients around the plant? Or is it just attracting insects to the plant? You decide.

The correct answer here is B and C.

Providing support for the plants, and transporting water and nutrients around the plant.

Those are the functions of the stem.

So here is your very first task.

You need to make some close observations of a celery stem.

Make sure to break it in a couple of places so you can observe the inside of the stem.

Hand lenses and microscopes could be used to help you make really close observations here.

So you need to really have a good look at the celery stem.

This is before you do anything else to it.

Record down some ideas about what it looks like.

Can you see if there are any marks on it? Are there any vertical or horizontal lines? If you break it in a couple of places, what do you observe about the inside? Is it all one colour? Or is there something different about it as well? Take some close observations and record what it is that you found.

Restart the video when you've done that.

How did you get on? Here are some close observations that were made by the children.

Your observations may have been similar or they may have been different.

Izzy says, I observed that the stem felt firm and there were leaves at the top.

Alex says, I noticed that there were lots of long stringy, fibres inside.

Oh, that's a good way of explaining, yes.

Little fibres there, which are quite difficult to cut.

And Aisha says, what did you observe? Did you observe anything different? Or did you observe the same as the two children here? Looking inside plants can be really fascinating, but hopefully, this is a job that can be done with a stick of celery this time and not just going around chopping any old plants up.

The second part of this lesson is called how water is transported in plants.

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

To make the food, they need water.

Jacob says, but leaves don't take in water.

How does the water get to the leaves? Hmm, that's a good question.

Is it like a straw? What do you think? How does the water get to the leaves? So how does water get to the leaves? What did you discuss? Let's find out more.

First, plants absorb the water they need from the soil through their roots.

There you can see an image of some grass, and there's roots going deep down into the ground there below the soil.

Roots are very, very important, as they secure that anchor point for the plant.

Or otherwise, it would blow away or be able to be ripped up far too easily.

So they absorb the water they need from the soil through their roots, and then the water is transported up through the stem to the leaves and the flowers.

Here you can see an example of another plant.

Water travels upwards through tiny tubes in the stem to the other parts of the plant.

I wonder if you were able to see some of these tubes inside the celery that you chopped up? Usually, these tubes are very small and thin, but sometimes they are big enough for us to see.

So you might have noticed these stringy tubes in the celery stems that you observed.

These are the bits that were described as being like stringy bits of fibre and may have been quite tricky to chop up.

Jacob says, well, I cut the stem and I could see the holes that the water travels through.

There you can see the stick of celery there, and there are lots of different holes there all around the top.

They're not everywhere, are they? They just seem to be around the surface of the larger curve at the top of the celery.

Stop and think.

How do plants take in water? Do they soak it up through their leaves? Do they collect rain in their flowers? Or do they absorb it through their roots? The correct answer here is C.

They absorb it through their roots.

How do flowers and leaves get the water that they need? Is it absorbed through the leaves and flowers when it rains? Is it transported from the roots up through the stem? Or is it made inside the leaves and sent around the plant? The correct answer here is B.

Water is transported from the roots and up through the stem.

We can see this as well in flowers.

We can add dye to the water we keep cut flowers in to observe how it's transported around the plant.

These plants have been cut at the stem.

Although they don't have any roots anymore, the stem will be able to take up some water from the glass.

We can observe how the plant changes over time to see how the water is moving around it.

Jacob has put some celery stems in water and added red or blue dye.

What do you predict will happen to these plants? Discuss that question and restart the video when you've done that.

So what did you predict was going to happen here? Well, stems are still very good at drawing water around the plant, but they're not as good at doing that job as the roots are.

It's essential for the roots to remain onto the plant to help the plant continue to spread water around the system.

Due to the fact that the stem isn't as good as the roots at doing this, we find that plants and flowers that have been cut in this way usually die after a short time because they start to shrivel up.

Whereas plants that have roots put in soil, in house plants, for example, usually survive for a lot longer.

Jacob has split another stem in half and put each half of the stem into a different colour of dye.

So what do you predict will happen to this plant now? Discuss.

Remember how we said that the stem wasn't as good at taking the water as the roots so eventually things will shrivel up and die.

That doesn't mean that it doesn't take anything at all.

So I wonder what kind of things are going to happen in this example here? We can trace where the water is going because it's been dyed blue and red.

We can then find out what will happen by observing each plant over time.

So I wonder how we can observe this.

Are we going to take some pictures? Are we going to do some drawings? Or maybe write down our observations? You decide.

Here is task B, and the first part is to set up an investigation into how water is transported into plants by placing some plants cut at the stem into water containing dye.

The second part is to make your prediction about what you think is going to happen.

I think.

Because.

Always give a reason why.

Step three is to observe your plants over time to see how they change.

You can use the celery idea that we've shared already, or maybe you'd like to come up with something of your own idea.

Good luck with your task.

Restart the video when you've done that.

So here is an example of an investigation.

It's Sofia's.

She says, here's my investigation.

Have you set yours up in a similar way? It was important here that we knew which flower was placed into which liquid and that the plant is in a place that's going to enable it to take water up through the stem.

Here's the second part.

Sofia says, I think the flowers will change colour to red or blue because the dye will be transported up the stem and into the flowers along with the water.

Lucas says, I think the leaves will change colour because they need water to make food, but I don't think the flowers will because they don't need water.

I wonder if your prediction is similar to theirs? Did you think that flowers didn't need water? Here's step three.

She says, I'm going to check my plants in three hours, six hours, and 24 hours to see if they've changed.

It's a good idea to set different increments there.

You might decide that you wanted to do it for shorter periods of time as well.

But you don't want to leave it for too long.

Otherwise, you might miss the process starting and finishing.

The final part of this lesson is called observing changes.

So Jacob has set up an investigation with one celery stem that has been cut and placed into two different colours of dye.

Here's Jacob, and here's his investigation.

What a good idea.

We can really track where this water is going now, can't we? What do you notice about Jacob's celery after four hours? There's one on the side which is very green.

That's the one at the start.

And there's one at the other side over there, and that's it after four hours.

What do you notice? Stop the video and discuss.

Restart when you've done that.

So using your keen scientific observing skills, what did you notice? Well, Jacob says, I noticed that the leaves on the side with red dye started to turn red, and the leaves on the side with blue dye started to turn blue.

Have a think.

What does this tell us about how water moves in plants? Discuss.

Well, I can see for one example that the right-hand side is blue and the left-hand side is red.

So that means one side of the stem does one side and the other side of the stem does the other.

Well, I didn't know that before.

Jacob says that this shows us that water moves upwards through the stem to the leaves of a plant.

So Jacob cut his celery stem.

There you can see an example of it.

You can see that one side is blue and the other side is, well, what do you notice? Pause the video here and discuss.

Restart when you've done that.

So one side is red and one side is blue.

You can see those tiny dots there.

They are the parts that are dragging the water all the way up through the plant.

Jacob spotted that as well.

I can see coloured dots.

These must be the tubes that the water travelled through to get to the other parts of the plant.

Fantastic.

I wonder if you noticed anything else? Stop and think.

Plants can be blank to find out more about how they change.

Observed over time, sorted into groups, or given scientific names.

The correct answer here is A.

Plants can be observed over time to find out more about how they change.

Here is task C.

Now you can use either your own results or Sofia's results here to discuss whether your prediction was correct, and why? Here are Sofia's results.

There's the plant at the start, the plants after three hours and the plants after six hours, and wow! There is definitely a difference there.

Sofia adds, I also left the plants overnight.

These are my results at 24 hours compared to three hours.

Oh, fantastic.

So use this further information here to add to your observations.

Restart the video when you've done that.

Jacob says, my prediction was partly correct.

The leaves did change colour like I thought they would, but the flowers changed colour too.

Sofia says, was your prediction correct? Yours could have been wrong or it could have been correct.

Or maybe a part of it was correct.

Often that's the case.

Often, there's something that has gone right and something that you might need to change in the future.

Here's the second part of task C.

Explain what our observations tell us about the way that water is transported in plants.

So use all your observations from these experiments here and tell us how does water get transported around plants? Explain it.

Restart the video when you've done that.

How did you get on? Sofia says, I observed my plant's leaves and flowers changing to the same colour as the dyed water.

They started to change colour after three hours and the colour got darker over time.

After 24 hours, the colour was really vibrant.

Jacob says, my observations tell me that water travels upwards through the stem to all of the flowers and the leaves on a plant.

I wonder if your observations were the same and what you summarised from all of this? Well done for completing those tasks.

Let's summarise our lesson.

The functions of a stem are to provide support for the plant and to transport water and nutrients.

Water is absorbed by the roots of a plant and then transported up the stem to the leaves and the flowers.

We can find out how water is transported through plants by observing them over time.

Well done for completing these different tasks today.

I hope that you were able to make some colourful predictions and some colourful observations about the different types of plants that you used.

Well done.

I've been Mr. Wilshire.

Thank you very much for listening.