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Hello, my name is Mrs. Mehrin and I'm so excited to be learning all about the conservation of plants using seed banks with you.
Let's begin.
Welcome to today's lesson from the unit Reproduction and Life Cycles: Plants.
Your learning outcome is, I can describe how different species of plants are being conserved by the use of seed banks.
Now I know that learning can sometimes be a little bit challenging, but that's okay because it just means we are going to work really hard together and we're going to learn some fabulous new things.
So before we begin, here are your keywords for today's lesson.
Alongside these keywords are your definitions.
Now I am going to be referring to these throughout today's lesson.
However, if you find it helpful, you can pause the video here and you can jot these down.
Off you go.
Fantastic.
Well done.
So let's begin with the first part, seeds and germination.
So flowering plants reproduce by making seeds after being pollinated.
What do you know about seeds? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So you might have said things like seeds are what is needed to make a plant grow.
You might have said that seeds can come in lots of different shapes and sizes just like in this picture here.
You may have said that some seeds are hidden within a plant or some seeds can be eaten like watermelon seeds and pumpkin seeds and strawberry seeds.
And you may have said, for example, with strawberry, but the seeds are on the outside of the fruit as well.
So lots of things that you may have said about seeds.
So seeds come in many different shapes and sizes.
And here we've got a pistachio seed, which has been cut in half, and an almond seed, which has been cut in half.
And you can see that they're slightly different shapes, but also completely different colours.
And most seeds have a hard outer casing or a shell just like this.
And inside is a very small plant ready to grow.
There we can see it in there and we can see it there in the almond seed as well.
Now, because the plant doesn't have any leaves to make food, seeds also contain a store of food, just there.
And this provides the new plant with the food it needs to get bigger and grow its own leaves.
Aren't they so clever? Now let's do a quick check-in of your learning before we continue.
So inside a seed's, outer shell there is a very tiny plant and a store of what? Is it A, pollen, B, food, C, water, or D, nectar? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is B, food.
Now germination is when a seed begins to grow and usually a root grows downwards out of the seed, closely followed by a shoot growing upwards.
Just like in this picture here.
So what is germination? Can you remember? Is it A, when a flower's seeds are dispersed away from the parent plant B, when pollen is moved from one flower to another by animals, or C, when a plant first starts growing from a seed? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
Let's see what the answer is.
It's C, when a plant first starts growing from a seed, just like in that picture that we saw, well done.
Now seeds have certain requirements, so requirements of things that need to happen to be able to germinate.
And Jacob says, "I know that plants need space to grow water, air, warmth, light, and nutrients from soil to survive and grow.
Do seeds need all of these things to be able to germinate?" What do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So seeds do need water, air, and warmth to germinate.
And if they don't have one or more of these requirements, it will not germinate and start to grow because it just doesn't have the things that it needs.
Lucas grew some sunflowers over summer and autumn and they formed lots of seeds just like in this sunflower here where you can see all of the seeds.
And the sunflower head is where all of the seeds are contained.
Now, Lucas knows it's going to be too cold over winter for his seeds to grow into new sunflowers.
He wants to keep the seeds until next summer and then plant them.
So Lucas says, "What can I do to stop my sunflower seeds from germinating now and then dying over winter?" What do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
Well, to stop his seeds from germinating, Lucas can make sure his seeds don't get all of the requirements for germination.
So Lucas says, "I'm going to make sure they stay dry." Because remember, we need water in order for a seed to germinate.
And Sofia says, "You should try to keep them cool too." So let's do a quick check-in of your learning, what do seeds need to be able to germinate? Is it A, light, B, water, C, nutrients from soil, D, air, or E, warmth? Remember, there may be more than one correct answer here.
Okay, off you go, Fantastic.
Well done.
The answers are B, D, and E.
So here is your first task for today and it says, explain how and where Lucas could store his seeds to prevent them from germinating.
So remember the three things that seeds need for germination, which is water, air, and warmth.
So where can Lucas store his seeds to prevent them from germinating and then he can plant them when it gets to summer? Okay, I'm going to give you some time now to do that.
So I'd like you to pause the video here and have a go at explaining.
Off you go.
Fantastic.
Well done.
So Lucas could keep his seeds in a sealed plastic box so they stay completely dry.
So that is eliminating the water side of germination.
He could keep the box in a cool place like an outdoor shed so they get very little warmth.
Also, that's going to stop them from getting too much air as well.
Now were your ideas similar to these or were they different? You could have decided to put yours in a different place or in a different container, for example, or you might have had other ideas to prevent water or moisture from getting onto the seeds.
Well done.
So now we are onto the second part of our learning, which is seed banks.
So conservation is the act of protecting earth's natural resources for current and future generations.
And to help with conservation of plants, seed banks have been set up around the world.
The act of protecting the natural world is called what? Is A, climate change, B, conservation, C, endangered or D, extinction? Can you remember? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is B, conservation.
Now, seed banks contain stores of many different types of seeds.
Why is conservation of seeds in a seed bank important? What do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Let's find out.
So sometimes plants and seeds can be lost due to natural or human made disasters such as flooding, fire or war.
And seed banks store a wide range of different types of seeds that can be replanted after disasters have destroyed plants and seeds.
And seed banks can be used to reestablish rare plants that have been lost through disasters and prevent species from becoming extinct.
Because there are so many animals and humans who rely on plants for survival.
And unfortunately, if we don't have those seed banks, it would mean that some of those plants would eventually become extinct.
And because of that, it would really affect animals and humans as well.
So it would have a knock-on effect for the whole world.
Now in 2020, bushfires in Australia destroyed much of the habitat for a rare type of herb called clover glycine.
Now the Millennium Seed Bank in the UK had a store of the seeds and sent 250 seeds over to Australia to help reestablish the plant in the wild.
And seed banks are also useful for carrying out enquiries into plants.
So scientists can use the seeds to research and develop crops that are more resistant to disease and that produce more food.
So let's do a quick check-in of your learning.
What are seed banks? Are they A, laboratories where rare seeds are grown B, places where seeds are conserved C, farms where seeds are carefully harvested.
I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is B, places where seeds are conserved.
Izzy says, "Why don't the seeds stored in seed banks germinate and grow into plants?" What do you think? Think about what seeds need in order to germinate.
And so why do the seeds in the seed banks not germinate and grow into plants when they've just been stored? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
Well, Lucas says, "Seeds in seed banks are stored in special conditions so they cannot germinate.
They are kept dry and cold so they can't get the water or warmth they need for germination." Now, seeds can survive for long periods of time if kept in the right conditions.
So scientists have even been able to germinate centuries old seeds that have been found deep in cold Arctic ice and inside the dry ancient Egyptian pyramids.
This means that seeds can be kept for many years in a seed bank and can be ready to grow into new plants if they are needed.
So we can go back to what happened with the Australian bushfires and the fact that because the UK had the seeds that they needed, even though the bushfires wiped out most of those plants, the UK was able to give some of those seeds from the seed bank and help for new plants to be grown in Australia.
Now there are over 1,000 seed banks across the world, each storing different selections of seeds.
The two largest seed banks are the Svalbard Global Seed Bank and the Millennium Seed Bank.
So this is the Svalbard Global Seed Vault and the Millennium Seed Bank.
And this Millennium Seed Bank is in the UK.
So seeds in seed banks are kept safe and prevented from germinating by keeping them what? A, cold and wet, B, cold and dry, C warm and wet, or D, warm and dry.
I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is cold and dry.
So now you are going to use secondary sources to research the world's two largest seed banks and complete the table.
So here is the table.
So you've got the Millennium Seed Bank and the Svalbard Global Seed Vault.
So you're going to research where the location is, when it opened, the date that it opened, the number of different types of seeds that they contain, the number of different types of seeds, the number of seeds, the temperature the seeds are stored at, and the example of seeds stored there.
So you're going to use your secondary sources to complete this activity.
So I'd like you to pause the video here and have a go at doing that.
Off you go.
Fantastic.
Well done.
So the Millennium Seed Bank is located in West Sussex in England, and the Svalbard Global Seed Vault is in Spitsbergen in Norway.
The Millennium Seed Bank opened in November, 2000 and the Svalbard Seed Vault opened in February, 2008.
There are 40,000 different types of seeds in the Millennium Seed Bank compared to 5,000 in the Svalbard.
The number of seeds is 2.
4 billion seeds in the Millennium Seed Bank compared to over 1 million in the Svalbard Seed Vault.
The temperature seeds are stored at as minus 20 degrees in Millennium Seed Bank and minus 18 degrees in the Svalbard Seed Vault so quite similar in temperature.
So some examples of seeds stored there, and you might have had different ones.
You've got the baobab tree and then Nymphaea thermarum.
And then in the Svalbard Seed Vault you've got rice, potatoes, and quinoa.
So now we are onto the summary of our learning today.
So seeds contain a tiny plant and a store of food to allow the plant to germinate and begin to grow.
Seeds require warmth, water, and air to germinate.
A seed bank is a place where seeds are kept safely to conserve different species of plants for the future.
You have worked so hard today and you've used your fantastic researching skills to find out about two of the world's largest seed banks.
You have done brilliantly, well done.