Lesson video

Hi, everyone, and welcome to this lesson from the Oak National Academy.

Today's lesson is all about cellular respiration.

I wonder what you already know about cellular respiration.

You've probably guessed where it takes place from the title.

That's right.

It takes place inside a cell.

Today's lesson is all about this incredibly important process, which takes place inside cells.

Hi there, I'm Mrs. Wheat.

And by the end of today's lesson, you'll be able to describe cellular respiration and explain why it happens in living organisms all the time.

It's really, really common to get confused by this process.

There's lots of misconceptions about it.

We're gonna spend a lot of time today looking at those misconceptions.

Really, really, really tackling them, and so hopefully, you won't get tripped up by them.

We're gonna look at our keywords now.

So, we've got cellular respiration, cell, mitochondria, glucose, and breathing.

I'm gonna show you the definitions for those keywords.

Please don't try and rush and memorise these now.

I'll explain each one of them in lots of detail as they come up in the lesson, but if it helps you out, feel free to pause the video here and read them or even copy them down, so it's easier for you to refer back to them.

Here they are.

Today's lesson is in three parts.

In the first part, we'll talk about cellular respiration, what it is, where it happens, and why it's important.

Next, we'll talk about plants and how important cellular respiration is for them.

And finally, we'll look at some of the key differences between breathing and cellular respiration.

But first of all, let's talk about what cellular respiration actually is.

Take a look at all of these living organisms. In the top row, we have some bacteria, a fish, a baby.

In the middle row, we've got an insect, a worm, some flowers.

And finally, we have an owl, some mushrooms, and a few trees.

All of these living things are so, so different.

Some have arms, others have wings.

Some eat, others photosynthesize.

Most of them are multicellular, but the bacteria consist of just one cell.

It's unicellular.

So, there's a huge variety of life here on my slide.

But even though they're incredibly different, they have so much in common.

What do you think? What are some of the things they have in common? Hopefully you can be a bit more creative than they're all made of atoms. Pause the video here and take a few seconds now to think of as many things as you can that they all have in common, and click play when you're ready to continue.

I bet you came up with some really brilliant answers.

I can't possibly go through every one of them that you might have come up with, so I'll just go through the ones I thought of.

Something these living things all have in common is they all carry out the same life processes.

There's a really useful mnemonic for remembering these life processes, which you might have come across in primary school.

Can you remember it? Pause and have a think of what it might be.

Well done if you remembered it, and no worries if you didn't.

Primary school was a long time ago for you, guys.

Each of these letters is the starting letter of one of the key seven life processes that living organisms carry out.

Pause here and see if you can remember what any of these letters stand for.

Right.

Let's see how much you remembered.

Movement, all living organisms move, even when they don't have muscles or bones to help them, all living things move.

Some cells have tails called flagella, which propel them forward.

And many plants such just flowering plants turn towards the sun during the day.

Both of these are example of moving, even if they happen so slowly that it's really difficult to see.

It still counts.

Right.

Next, reproduction.

All living things reproduce.

Some animals become pregnant, others lay eggs.

Cells divide, and split into two new cells.

There's lots of different ways of reproducing and all living things do it.

Sensitivity, all living things are sensitive and change depending on what is happening in their environment.

Plants, for example, are sensitive to sun and to gravity and can turn and grow depending on those things' availabilities.

What we've got next.

We've got growth.

All living things grow.

They grow, they get bigger, they get older.

All living things, that happens to.

Right.

Next, we have respiration.

I won't go into too much detail about that one now, because that's what we're spending the whole lesson on.

Next is excretion.

What does excretion mean? Pause and have a think about that.

Great job if you remembered.

Excretion is about removing waste.

So, all living things need to remove waste products in order to stay healthy and to not be poisoned by some of these harmful waste products.

So, excretion or to excrete, that's something we all do as well.

Okay, what's the last one? It is nutrition.

All living things need some form of nutrition in order to survive.

Lots of animals eat using their mouths.

Plants make their own food during the process of photosynthesis and decomposers like fungi, like the mushrooms on the screen here.

And some bacteria use special chemicals called enzymes to break down decaying matter and gain nutrients from what they're breaking down.

So, there's lots of different ways of gaining nutrition, not just eating and digesting.

It all counts, though.

They all need those nutrients to survive.

Okay, so these were our seven life processes that all living things do.

So, hold on just a second.

I thought this lesson was about respiration.

Why have I spent all that time talking about the seven key life processes? What has that got to anything? Well, cellular respiration provides the energy for all of those life processes.

So, movement.

Living things like animals wouldn't be able to move if they didn't have energy to contract and relax their muscles and move their skeleton.

Growth, growing, living things can't grow unless they have energy they need.

Sensitivity.

Living things wouldn't be sensitive of their surroundings or where their surroundings and be able to respond to them.

So, for us, that we do that by seeing things, hearing things, touching, feeling, and tasting.

We couldn't do any of that if we didn't have energy we need from cellular respiration.

So, none of the other six key life processes could take place without cellular respiration.

It's so important that it is constantly taking place in every cell of every living organism.

If a cell stops respiring, eventually, it will die.

So, hopefully, that's really clear.

You should get that cellular respiration is really, really important.

We need it for energy.

So, let's look at it as a process in more detail now.

Cellular respiration is a chemical process that uses glucose from food as a fuel to provide energy for life processes.

Glucose is a sugar that our cells use as fuel.

We get it from eating carbohydrates and sugar.

So, if you look at my pictures, we've got some potatoes, we've got some gummy bears, we've got some rice.

All of those are examples of where we can get glucose from, from our diet.

So, we've got the potatoes and the rice.

Those are complex carbohydrates.

During digestion, we break those down into glucose and other things, and then our cells can use that glucose for cellular respiration.

We've got the gummy bears, which are more simple sugar, really, really fast-acting.

And again, our body uses that as well, break it down slightly less, but ends up as glucose, just the same and then some other stuff.

And yeah, we, ourselves, can use that as a fuel as well.

So, all those things get broken down into glucose, our cells are very happy with that.

So, where does that all happen then? What is this? Do you recognise this? Pause and have a think.

Give me as much detail as you can.

It's a cell.

It's an animal cell.

Great job if you got that.

Cellular respiration takes place inside every cell of every living organism.

All of your cells right now are hard at work respiring, using the glucose that you've eaten previously as a fuel.

And we're gonna talk about the two parts of the cell, which are particularly important to respiration.

So, we've got the mitochondria and cytoplasm.

So, within a cell, cellular respiration can take place in, inside the mitochondria and cytoplasm of animal and plant cells, and inside the cytoplasm of organisms that don't have mitochondria such as bacteria.

So, that's why those places are so important to cellular respiration.

It's where it takes place.

So, that's actually the first part of today's lesson done.

We're gonna check you understood that, and then we'll put it into practise.

So, for our learning check, you're gonna see some statements and you're gonna tell me how you feel about them.

You can either say you are sure it's right, you think it's right, you think it's wrong, or you are sure it is wrong.

Okay.

So, here are statements.

A, respiration provides energy for life processes.

B, respiration involves chemical reactions.

C, only some living organisms respire.

Pause the video here.

What you think of those answers? Let's go through the answers.

So, A, that was right.

B, that was also right.

And, C, that was wrong.

All living things need to respire.

All living organisms need to respire to stay alive, 'cause they need energy.

Right.

Let's do a few more.

So, how do you feel about D? Respiration takes place in muscle cells only.

E, if respiration stops happening in an organism, the organism will die.

Pause and think about your answers.

Let's see how you did.

Right, D, that is wrong.

Respiration happens in all cells all the time, not just muscle cells.

Let's look at E.

That is correct.

Organisms need cellular respiration to stay alive.

Hopefully I've made that super clear.

Right.

Okay, let's move on to our first practise task.

Right.

Alex has written some notes about cellular respiration, but there are some mistakes.

So, to be clear, we're talking about scientific misunderstandings, not spelling and punctuation errors.

If there are any of those kinds of errors, those are accidental.

We're just looking at, he's got some of his science of it wrong.

Every line of his notes contains one mistake.

Identify the mistakes and rewrite his notes.

So, here are his notes, he thinks some living organisms carry out respiration.

Cellular respiration occurs in some cells of a living organism.

It occurs inside cells called mitochondria.

In cellular respiration, water is used as a fuel.

This provides oxygen for life processes to occur.

So, find those mistakes, and then rewrite those notes correctly.

Okay, pause the video for a few minutes while you have a go at that.

Good luck, everyone.

Let's see if you've got all those mistakes.

Right.

All living organisms carry out respiration.

It's one of key seven life processes.

All of them do it.

Cellular respiration occurs in all cells of a living organism.

It occurs inside parts of the cell called mitochondria.

So, mitochondria inside animal cells and plant cells.

They're not cells by themselves, they are inside cells.

In cellular respiration, glucose is used as a fuel, not water.

And this provides energy for life processes to occur.

Really, really great work.

Great job.

We're doing really well.

Right.

We've talked about cellular respiration, what it is, where it takes place, and why it's so important.

Now, we're gonna learn about how important cellular respiration is for plants.

So, plants are living organisms as well, and not everyone understands that.

I wonder if it's because we can't see them doing things like moving, even though they do move, we can't see them responding to their environment.

But they do fulfil all of those seven (indistinct) grand key life processes that they are alive.

They do move.

Have a look at this picture.

You can see the plant there is wrapping itself around the support.

Those vines are moving, so they can hold on and grip.

That's an aspect of being alive.

We've got reproduction, plants reproduce.

Do you know what those are? Pause the video and have a think.

What is that? They're seeds.

I really hope you've had the experience of planting a seed and watching it grow.

So, that's part of how plants reproduce.

So, they definitely reproduce, just in a different way to the way that animals do.

Right.

Next, sensitivity.

What's that plant doing? It's leaning.

It's tilting.

Why is it leaning and tilting? It's tilting.

It's growing towards the light.

That's part of how it's sensitive, how it responds to its surroundings.

And finally, grow.

I've already said that in reproduction, but plants grow really.

If you haven't had a chance, get some crest seeds, watch them grow, and eat them afterwards.

You can't eat all plants, but you can eat crests.

But yeah, it's really, really rewarding to watch a plant grow.

So, they also need to carry out cellular respiration.

So, they have energy to do all of these things that they need energy.

So, if plants can't carry out cellular respiration, they won't have the energy they need for life processes and they will die.

All parts of the plant need to carry out cellular respiration as all parts of the plant need energy.

What do you think is happening in this diagram? Pause the video here whilst you think about that.

It's a food chain and it's showing that the cow gains its energy for life processes from the grass.

Humans gain that energy for life processors from eating animals like cows.

They're not perfect diagrams. For example, I know that a lot of you won't eat beef or maybe you just don't eat any animals at all.

But they are really useful at showing us relationships between living organisms. So, animals get glucose from eating other animals or plants.

So, like the cow is eating the grass, the humans eating the cow in this diagram.

Plants don't eat.

They create their own glucose in a process called photosythsis.

So, they get their glucose in a different way, but they still need glucose.

Glucose is still the fuel for cellular respiration in plants.

Right.

Who knows what this is? Be as specific as you can.

Pause and think about that.

It's a plant cell.

Well done if you got that right.

Plant cells, just like other types of cells, use glucose to provide energy for life processes.

They carry out cellular respiration using oxygen from the air and glucose from photosynthesis.

So, there's the mitochondria in the bottom corner of my plant cell.

We've got oxygen going in from the air.

We've got glucose going in, that's coming from photosynthesis.

This takes place in the mitochondria.

So, same as it does in animal cells and other types of cells, it happens in the mitochondria as well.

Right.

Hopefully that all made sense to you.

Let's check and let's practise that.

In which parts of the cell does cellular respiration take place and when? Connect two boxes.

So, draw one line and connect two of those boxes.

Pause the video here whilst you do that.

Let's see if you got that right.

So, you should have connected mitochondria and all the time.

Great work.

Let's do our practise task now.

Sam, Aisha, and Izzy are having a discussion about where plants get energy they need for life processes.

Sam says, plants aren't alive so they don't need energy.

So, they don't need to carry out cellular respiration.

Aisha says, plants are alive, but they get energy for life processes from photosynthesis.

Izzy says, plants get energy for life processes from cellular respiration.

Decide if each person's understanding is correct and explain why or why not.

Pause the video here for a few minutes once you have a go at that.

Right.

Let's see how you did.

Sam is wrong.

Plants are alive and do need energy.

They do carry out cellular respiration.

Aisha is right in saying that plants are alive.

However, Aisha is wrong in saying that plants carry out photosynthesis to gain energy for life processes.

They do photosynthesis to get glucose, which is the fuel for cellular respiration.

Photosynthesis is a process that creates glucose.

Izzy is right.

Plants gain the energy from life processes from cellular respiration.

Right.

Great work if you got that right.

So, what have we done so far? First, we looked at the process of cellular respiration, what it is, where it takes place, and why it's important.

Then, we talked about how important cellular respiration is for plants.

And finally now, we'll talk about the key differences between breathing and cellular respiration.

So, breathing and cellular respiration are different processes.

It's really, really common to get them confused, but they are different.

Breathing is a mechanical process in which muscles contract and relax to move air in and out of the lungs.

No chemical reactions are taking place.

So, what I mean by mechanical processes, things are physically moving, like how I'm moving my arm right now.

And no reactants are turning into products and me moving my arm, it's just moving.

That's what's happening in breathing, our muscles like contracting and relaxing, forcing air in and out of our body.

No reactant, no products, no changing.

So, not all living organisms breathe.

That's something that's really important actually.

So, I've got a bacteria and a plant.

Those things don't breathe, so you don't need to breathe in order to be considered alive.

So, let's look at that in contrast to cellular respiration.

So, cellular respiration uses glucose from food as a fuel to provide energy for life processes.

That's a very different definition to breathing.

Nothing to do with the lungs, nothing to do with air.

So, it's a series of chemical reactions.

So, reactants are turning into products.

There's a lot of change going on there.

And it occurs in every cell of every living organism.

So, you don't need to be alive.

Well, sorry, you don't need to breathe in order to be considered alive, but you do need to respire in order to be a living organism.

So, hopefully, that's given you a picture of just how different they are.

They are related, so I'll go through that.

But remember that separate processes happen in different places, achieve different things.

Right.

We breathe in air and this provides the oxygen we need for cellular respiration.

Oxygen, along with glucose that we gain from food, is transported to our body cells via our bloodstream.

Oxygen and glucose diffuse into the mitochondria of our cells.

They are used in cellular respiration to provide energy for life processes.

So, yeah, they're related.

Breathing provides the oxygen we need.

It's really common to get them confused.

So, don't worry if you've done it before.

If you do it again, just kind of keep asking yourself, where does this process take place? Is it a chemical process? What's the point of this process? And hopefully, that will help you to start to tell them apart.

Right.

Let's do our final round of checking if we understood and putting that all into practise.

Complete the sentences below.

You should only use the word respiration or the word breathing to fill in each of these gaps.

So, we've got moving air into and out of the lung is called, using food as a fuel to provide energy is called.

So, blank happens in all living things.

Blank only happens in some living things.

Blank does not happen in plants.

Blank provides living things with oxygen for blank.

Right.

Pause the video, fill in those blanks.

Let's go through the answers.

Moving air into and out of your lungs is called breathing.

Using food as a fuel to provide energy is called respiration.

Respiration happens in all living things.

Breathing only happens in some living things.

Breathing does not happen in plants.

Breathing provides living things with oxygen for respiration.

Well done, guys.

Right.

Let's look at our final practise task.

Amber goes swimming after lunch.

She wants to find out how long she can stay under water at the bottom of the swimming pool.

She doesn't know, oh, so she knows.

She knows she won't be able to breathe underwater, so she takes a deep breath first.

Amber's deep breath and her lunch will both help her body to keep her working underwater.

Use the word provided to complete the concept map on the worksheet.

Okay, so take some time now.

Complete that worksheet.

Good luck.

Let's look at your answers.

I'm gonna do the deep breath side first.

So, air, which is taken into the body by the process of breathing, which fills the, oh, lungs and provides oxygen.

Lunch provides food which is taken into the body by the process of eating, and it's broken down by the process of digestion, which provides glucose.

So, the oxygen and glucose are coming together in the blood, which carries it to the body cells, where is used as a fuel for cellular respiration, which provides energy.

Great job summarising everything we've learned today and that really, really good work.

We've talked a lot about cellular respiration today.

You should have a much better understanding of what it is and how important it is for all living organisms. Let's recap what we've learned.

Cellular respiration is a chemical process that uses glucose from food as a fuel to provide energy for life processes.

Cellular respiration happens in all living organisms all the time to provide energy to keep them alive.

Breathing in cellular respiration are different processes.

Breathing is a mechanical process that occurs in the lungs.

Cellular respiration is a chemical process that takes place inside the cells of living things.

Well done on all your fantastic effort today.

Have a bit of a break now and I'll see you back soon for our next lesson.