Lesson video

Welcome to today's fifth lesson in the unit ecosystems. My name's Mr. Jarvis, and I'm gonna be teaching you today.

Today, we're looking at ecosystems and habitats.

By the end of today's lesson, you should be able to describe what makes an ecosystem, you should be able to identify the features of habitats, and just should be able to explain how organisms are adapted to live in their habitat.

During the lesson today, there are five key words, they're ecosystem, habitat, adaptation, biotic, and abiotic.

Here are the definitions of those words that are appearing on the screen.

You can pause the video if you'd like to read through them, but don't worry, we'll cover what they mean as we go through the lesson.

Today's lesson is broken down into four parts.

First, we're going to look at what ecosystems are.

Then we're going to look at what habitats are, and the features of different habitats.

We're then going to move on to how organisms interact with their habitat.

And finally, we're going to look at some adaptations of different organisms, and in particular adaptations that help with changing environments.

So if you're ready, let's get started with our first part, understanding ecosystems. So an ecosystem is made up of all of the living organisms that live in a place.

It also includes the interactions between different types of organisms. And it involves the interactions that organisms have with the place that they live, the non-living parts, so things like the rocks, the soil.

The word ecosystem can be broken down.

Eco means to relate to the environment, and a system is how a group of things work together.

So the word ecosystem means things that relate to the environment that work together.

Ecosystems can vary in size.

The largest ecosystem is the planet earth itself.

However, ecosystems can be much smaller.

For example, this bottle garden is also an example of an ecosystem.

The living parts of an ecosystem are made up of communities, and a community is the interaction between populations of different organisms that live in a specific area.

So to give you some examples, here's a rainforest community, here's an African grassland community, and here's a coral reef community.

You can see the different populations of organisms all interacting together.

A population is the number of organisms of one type that live in a specific area.

So for example, the population of humans that live in a city, or the population of pelicans that live on a lake.

Here are some examples of some of the non-living parts of an ecosystem.

Things that are non-living that impact on the organisms that live in an ecosystem include the soil, rocks, water, air, light, litter, and pollution.

All of those things, and more, can impact the organisms that live within an ecosystem.

So here's our first check of the lesson.

I'd like you to match the words in the boxes below to the correct descriptions.

So the words are ecosystem, community, and population.

And the descriptions are the number of one type of organism in a specific place, the interacting living organisms and non-living parts in a place, and the interacting populations of living organisms in a place.

You might need to pause the video when you've matched your words with the descriptors.

Then press play, and we'll see how well you've done.

Good luck.

So how well did you do, let's see.

An ecosystem is the interacting of living organisms and non-living parts in a place.

A community is the interacting populations of living organisms in a place.

And a population is the number of one type of organism in a specific place.

Well done if you've got all three of those right.

So now let's practise what you've learned.

Sam has been asked to describe two ecosystems. These are the ocean and the tropical rainforest.

He'd like you to help him.

You need to think about the characteristics of both ecosystems. How would you recognise each of the ecosystems? Think about the organisms that live there, and the non-living parts of the ecosystems. When you've done that, write a short paragraph to describe each ecosystem to Sam.

Remember, think about the living and the non-living parts.

You'll need to pause the video, write your paragraph, and then when you're ready, press play, and we'll check your answers.

Good luck.

So how well did you do, let's check your answers.

Here are some of the living and non-living features of these two ecosystems. We're gonna start with the ocean.

The living parts of the ocean are lots of fish and marine animals.

There's also lots of plants, but these are only near the shore or the surface.

The non-living parts are salt water and light reducing as you go deeper into the ocean.

Finally, they're big, wide, open spaces, and that means that the water itself can be quite rough and turbulent.

What about the tropical rainforest? The living parts of the tropical rainforest include lots of plants and animals, and there's lots of organisms that live in trees in a tropical rainforest.

The non-living parts are that it's warm, there's lots of rainfall, and light is reduced near the forest floor.

Look at the picture of the tropical rainforest, you can see it's much darker near the forest floor compared to up in the treetops.

Well done if you've got any of those answers, and you may have got other things for yourself.

So we're now going to move onto the second part of the lesson, and that's all about habitats and their features.

So if you're ready, let's get started.

So habitats are the places where organisms live.

They provide the conditions that organisms need to be able to survive.

And in order to be a habitat, they must provide food, shelter, and a place to reproduce.

Habitats vary in size, the largest habitat on earth is the ocean.

Other large habitats include forests, including tropical rainforests, deserts, frozen tundra, grasslands, and polar regions; the Arctic and Antarctic.

But some habitats can also be really small, and we call those micro habitats.

Micro means small or tiny.

Examples of micro habitats could include under plant pots or blocks, manmade temporary pools, or inside fallen trees.

Here are some pictures, and you can see that there's organisms living under pots and the rocks.

There's also a temporary pool in an old tyre.

And inside a tree trunk is a perfect place to provide food, shelter, and a place to reproduce.

Living organisms within the community interact with each other in the habitat.

For example, organisms eat each other, they eat other organisms to get their food.

There's competition between organisms to get the best shelter.

Here is a picture of lots of bats sheltering in a tree.

And organisms interact through reproduction.

Habitats also contain non-living parts, which can differ in different habitats.

So for example, we can look at different water or aquatic habitats.

In the ocean, we've got lots of salt water.

A river is made of fresh water, and it sometimes moves or flows.

A stream is made up of fresh water, and that often moves really, really quickly.

And a lake is made up of fresh water, but it's often still.

So you can see there are different non-living parts to the water, different physical features that make the habitat what it is.

So let's check to see how well you've understood that last section.

Which of the following statements best describes a habitat? Is it the interaction between living things in a place, the place where organisms feed, shelter, and reproduce, or the interaction between the living things and the non-living things in a place? Pause the video if you need to.

When you're ready, press play and we'll check your answer.

So the correct answer is B, a habitat is the place where organisms feed, shelter, and reproduce.

Well done if you got that.

Let's practise what you've learned.

I'd like you to look at the picture of the rock pool.

A rock pool is a habitat, it's a place where there's food, shelter, and a place to reproduce.

I'd like you to write a short paragraph to explain how the rock pool provides organisms with food, shelter, and a place to reproduce.

Pause the video, write your paragraph, and then when you're ready, press play, and we'll check to see how well you've done.

Good luck.

So how well did you do? I hope you didn't find it too hard.

How do rock pools provide organisms with food, shelter, and a place to reproduce? Well, the rocks first of all provide a firm base for seaweeds to attach themselves.

The seaweed is a producer, and that means that there's food for organisms that are found in a rock pool.

Food web diagram.

Cracks in between the rocks, in seaweeds, and under boulders provide organisms with shelter when the tide comes back in, and also provides places for organisms in the rock pool to reproduce.

Well done if you've got some or all of those, or if you actually got some additional answers for yourself.

We're now going to move into the third part of today's lesson, which is all about interactions within habitats.

So if you're ready, let's move on.

Organisms interact with other organisms in their habitat, for example, for food and to reproduce.

Living things that affect other living things are called biotic factors.

So a biotic factor is a factor that links to living organisms. So here's an example, a bear feeding on salmon.

The bear, a predator, is catching its prey, a salmon, and the salmon is living.

So feeding is an example of a biotic factor.

Living things that are affecting other living things.

Organisms also interact with the non-living parts of their habitat, for example, for food or for shelter.

So non-living, things that affect living things are called abiotic factors.

Here's another example using the same bear, the bear is catching its food in the river.

The bear is interacting with the river to hunt for food.

And the river is not living, so the river is an example of an abiotic factor.

So abiotic factors are non-living things that affect living things in their habitat.

Abiotic factors are measurable characteristics of the ecosystem in which an organism lives.

So examples of those abiotic factors include things like soil type, the intensity of light, the availability of water or humidity in an ecosystem, the climate and the temperature, or the altitude or levels of oxygen.

All of those things are abiotic factors which will impact the living things within an ecosystem.

Let's check to see how well you've understood that.

Sam has been given some cards listing some biotic and abiotic factors.

Can you help him to sort them into two piles, one containing the biotic factors and the other the abiotic factors? Pause the video, sort your five cards into two piles, and then when you're ready, start, and we'll check to see how well you've done.

Good luck.

So how well did you do? Well, the biotic factors are disease and competition for food.

Diseases are caused by living things.

And there's competition for food, so organisms are competing with each other to eat the food that they need to survive.

The abiotic factors are the levels of light, the temperature, and oxygen levels.

Well done if you've got those.

So let's now practise what you've learned.

Salmon live in the open ocean.

They swim upstream in fast flowing rivers to reproduce.

And here's a picture of a salmon swimming up a fast flowing stream in order to reproduce.

Salmon eat small animals and fish in the ocean, as well as small fish, crayfish, and worms in rivers.

I'd like you to write a paragraph to explain how the salmon is adapted to both habitats that it lives in, the ocean and the fast flowing rivers.

Think about the adaptations that help the salmon to interact with the biotic and biotic factors to survive in these habitats.

Pause the video, have a go at writing your paragraph, and then when you're ready, press play.

How is the salmon adapted to both habitats that it lives in, the ocean and fast flowing rivers? Things that you might have written about include having sharp teeth to help catch and eat prey, having good eyesight to help spot and catch the prey, having muscles to help it swim fast to help catch prey, escape predators, and to swim against the current.

It's got a streamlined shape to help the salmon move through the water more easily.

And its camouflaged to help it blend into the surroundings, to prevent being eaten or spotted by predators.

Well done if you got those right.

So that brings us to the final part of the lesson, which is all about adaptations and changing environments.

So let's go.

In order to survive in a habitat, organisms need special features, which are called adaptations.

Now, adaptations can be lots of different things.

They can, for example, help with everyday activities such as feeding.

Here are four pictures of birds, each of which have different adaptations to help them feed.

Flamingos filter water to get the krill and the small shrimps to feed on.

Birds of prey use their beak to tear the flesh off organisms that they've hunted.

The grebe has a sharp, pointy beak that helps it to fish.

And the blue tit catches small caterpillars and other insects with its short beak.

Organisms also have adaptations that help 'em to survive in specific habitats.

So here are four pictures of organisms that live in a desert.

A camel hoof spreads out over the sand to stop further the animal from sinking in.

The spines on a cactus help to prevent it from being eaten.

A meerkat digs a hole in the the sand to help shelter it from the extreme heat.

And the aloe vera has short, stumpy leaves that are filled with water, and that helps to conserve the water in the hot, dry atmosphere of the desert.

Some common adaptations help organisms to make their own food, to hunt for and eat food, to avoid predation by being camouflaged as this crab is in the picture, to move, to build shelters for protection, and to keep warm or cool.

So in the picture, you've got a seal, which has a large layer of fat around its body to help keep it warm in the cold, icy water.

A dog panting, and that's one way that dogs use to keep themselves cool.

And a crocodile, which is sunbathing in the warm sunshine to help warm its body up, to help it to move around.

Adaptations are inherited from parents, and when environments change, it can take a long time for adaptations to come into play to adapt.

And if the environment changes too much, organisms may become extinct.

Here's one example, a killifish.

They're often seen in aquariums, and they come from America, the USA.

In the 1980s, they were able to really quickly adapt to highly polluted water.

They were the only fish to be able to survive the pollution.

When organisms are removed from food webs, all other organisms in the food web are impacted too, and they can become extinct or endangered.

So let's check to see how well you've understood that last section.

The class have been learning about camels, and they've learned about camels being adapted to live in a desert habitat.

And the class have noticed that camels have long eyelashes, and these are shown in the picture on the screen.

They talk about why this is an adaptation.

Who of the classmates is right in their explanation.

Andeep says, "The eyelashes help to keep bright sunlight out of the eye to help the camel see better." Jacob says, "It isn't really an adaptation, as many mammals have eyelashes." And Sophia says, "The eyelashes help to keep sand out of the camel's eyes in a sand storm." Who's right? I'll pause for five seconds, but if you need longer, please pause the video, and then press play when you're ready to move on.

So the correct answer is Andeep, "The eyelashes help to keep bright sunlight out of the eye to help the camel sea better." And also Sophia, "The eyelashes help to keep sand outta the camel's eye in a sand storm." Well done if you've got both of those answers right.

So let's now practise what you've learned.

First of all, three different types of habitat are shown in the images below; you've got a tropical rainforest, a polar habitat, and a desert.

Choose an organism, an animal, or a plant that lives in each of the habitats, and write a short paragraph to explain how your chosen organism is adapted to live there.

If you're struggling, then here are some example organisms for you to use for your adaptations.

So we've got a lemur that lives in a tropical rainforest, a penguin that lives in a polar habitat, and a cactus that lives in a desert.

But try and think of your own examples if you can.

Secondly, global warming is causing the ice in polar habitats to melt.

What impact will ice melting have on the penguin population? As a hint, think about the impact on the population, and also the adaptations that penguins have to survive in that habitat.

You'll need to pause the video at this point.

Write your answers to the two questions, and then when you're ready, come back and we'll see how well you've done.

Good luck.

So how well did you do? Adaptations for the organisms. I've used my example organisms here.

The lemur in the tropical rainforest has a large tail to help it balance.

It has claws to help it grip and climb, and eyes are facing forward to help it judge distance when it jumps.

The penguin lives in the polar habitat.

It has a fatty body to help it insulate itself against the cold.

It has webbed feet and wings to help it swim.

And it has a streamlined shape that help it move through the water.

Its beak is pointed, and helps it to catch fish.

The cactus lives in a desert habitat.

Its leaves are adapted to spines to protect it from being eaten.

And it stores water in the stem, deep roots help to collect water.

I hope that you got those right, or if you did your own examples, that you can now link some of those features and adaptations to the habitats in which your organism lived.

The second question is about global warming causing the ice to melt in polar habitats.

And you're asked to answer, what impact will ice melting have on the penguin population? Well, the changing habitat may not provide the penguins with food, shelter, and a place to reproduce, and that means that the population could decrease, or even become extinct.

But penguins are able to swim well, and so they will still be well adapted to a life in the water.

However, they may be too well insulated for the warmer weather.

Well done if you've got any of those answers right.

So that brings us to the final part of today's lesson, which is the summary.

This is what we've covered in today's lesson.

We've seen that ecosystems are made up of the interacting living organisms and non-living things in a place.

We've seen that habitats provide organisms with food, shelter, and a place to reproduce.

We've covered that living things that affect other living things in a habitat are known as biotic factors.

And that the non-living things that affect living things are called abiotic factors.

We've seen that organisms have a range of different adaptations to help them survive in their habitats, and that changes to the environment may make it harder for organisms to survive in that particular habitat.

Thank you for joining us today.

I hope you've enjoyed it, and I look forward to seeing you again soon.