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Hello, my name is Mrs. Mehrin and I'm so excited to be learning all about selective breeding of plants 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 selective breeding can be used to create improved plants." Now I know that learning can sometimes be a little bit challenging, but that's okay 'cause it just means that we are going to work really hard together and we're going to learn some fabulous new things.
So let's begin.
So here are your key keywords for today.
Alongside these keywords are the definitions.
Now I am going to be referring to these throughout today's video.
However, if you find it helpful, you can pause the video here and you can jot them down.
If you'd like to do that, you can do that now.
Off you go.
Fabulous.
Well done.
So our learning today is split into two parts.
Let's begin with the first part, "Characteristics of Plant Offspring." Now many plants can reproduce sexually whilst using pollination.
I want you to explain to a partner what pollination is and why it's important for plants to be able to reproduce.
So I'd like you to pause the video here and have a go at doing that.
Off you go.
Fantastic.
Well done.
So pollination is when pollen from the anther of one flower is transferred to the stigma of another flower.
Here we have the pollen and it gets transferred from one flower and then to the stigma, which is like a sticky part of the flower.
And you can see it on the second flower here, where the arrow is pointing to.
That is the stigma, and it has this sticky substance on it, which allows for the pollen to stick to the flower without the wind, for example, being able to rub it off.
Now pollination leads to fertilisation and then to new seeds being formed.
The seeds will then be dispersed from the parent plant and will eventually grow into new plants.
Now, pollination occurs when pollen from the anther of one flower is transferred to what is A, to the petals of another flower; B, to the anthems of another flower; or C, to the stigma of another flower.
I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is to the stigma of another flower.
Now Alex has been learning about how plants reproduce, and he says, "I know that animals of the same species can have different characteristics to each other.
For example, humans can be tall or short and they can have differently coloured hair and eyes.
Do plants in the same species have different characteristics too?" What do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So let's find out.
So plants in the same species can also have different characteristics from each other.
And here we have some tomatoes with different characteristics.
So I can see in these tomatoes that the sizes are different.
The shapes are different, the colours are different, and even the leaves on the tomato are slightly different from one another.
And different tomatoes can have different flavours as well.
So if it's a plant that you can eat, you'll notice that they might have different flavours too.
So sometimes with tomatoes you might get some that are very sweet and some that are not as sweet.
Same with watermelon or strawberries.
Sometimes you might buy a punnet of strawberries.
And even within that one punnet of strawberries, there might be some that are sweet and some that are not.
Some that are big, some that are small, some that are slightly different colours.
So this is all very normal and plants in the same species can have different characteristics from each other.
So let's have a read of what it says here.
It says the size, shape, and colour of leaves, flowers, and fruit are examples of characteristics of plants that can be different between individuals of the same species.
Just like people as well.
So have you ever noticed that some strawberries taste sweeter or are juicier than others? And you might have observed that some are round and some are more pointy at the end.
And sometimes you can get some really crazy shapes of strawberries too.
So this is partly down to the characteristics of the strawberry plant that they come from.
Now, just like humans and other animals, plants get their characteristics from their parents.
And Alex says, "I have a combination of characteristics from my two parents." So here are Alex's parents and we can see, for example, Alex gets his eyesight from his dad because they're both wearing glasses.
I can see that Alex's mom has got the same coloured hair as him, and I can see that Alex's mom has freckles and Alex also has freckles.
So you can get a lot of characteristics from your parents, and often it's a combination of both parents.
In fact, you will always have something from each of your parents even if you tend to look like one parent more than another.
Now plant offspring grown from seeds will have a combination of characteristics of their two parent plants just like humans.
And here we have some pansies with different characteristics.
So we are onto the first task of your learning today and it says, are these statements correct or incorrect? So, A, pollination is when pollen from the anther of one flower is transferred to the stigma of another flower of the same species; B, plants grown from seeds have two parent plants; and C, plants grown from seeds have their identical characteristics to their parent plant.
And as you look across the top here, you will see the different statements.
So you need to have a look at the statements on the side and match them up to the sentences that are on the top.
So, "I am sure this is correct." "I think this is correct." "I think this is incorrect" and "I'm sure this is incorrect." So where do each of these three statements fit? So I'd like you to pause the video here and have a go at doing that.
Off you go.
Fantastic.
Well done.
So for A, you could have had, "I'm sure this is correct," or "I think this is correct." Either of those two options would be fine.
For B, it's the same.
"I'm sure this is correct" or "I think this is correct." Again, you could have either of those.
And the last one, "I think this is incorrect" or "I am sure this is incorrect." Well done.
Now the second part of your activity for task A is to rewrite the incorrect statements so that it's correct.
So plants grown from seeds have identical characteristics to their parent plant.
So I want you to rewrite that statement so that it's correct because currently it's wrong.
Okay, so I'd like you to pause the video here and have a go at doing that.
Off you go.
Fantastic.
Well done.
So plants grown from seeds will have a combination of features from their two parent plants.
This combination of features, they don't have to be identical.
So now we are on to the second part of your learning today, which is "Selective Breeding of Plants." So Alex is fascinated to learn that pollination can produce plant offspring with a combination of characteristics from their parent plants.
And Alex says, "I read that parent plants can be specially chosen to create more desirable offspring, and that this is called selective breeding." So selective breeding is done by individuals with desirable characteristics and breeding them together to create offspring who also have the desirable characteristics.
So those things that you really want to see in a plant.
So for example, for strawberries, it might be the sweetness of them or the shape of them that you might like the shape or the sweetness of one type of strawberry.
And so breeding them together with another strawberry which also has the same desirable characteristics, means that the offspring will also have those desirable characteristics.
So that's called selective breeding.
And so this is useful for farmers and others who grow crops to sell.
So what sort of characteristics are desirable for crops? So I've given you some when I spoke about the strawberry, can you think of anything else? So what do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So let's do a quick check-in of your learning before we continue.
So selective breeding is A, taking cuttings from the best plants to create more identical plants; B, creating offspring from parents who have desirable characteristics; or C, choosing seeds which look the largest to plant and germinate.
Again, I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So, the answer is B.
Now farmers can selectively breed plants to create new varieties of plants with more desirable features, such as more or larger fruits, pest or disease resistance, and larger flowers or more attractive flowers.
Now let's do a quick check-in of your learning before we continue.
Selective breeding of plants can create new varieties of crops with desirable features such as A, smaller volume of fruits; B, less tasty vegetables; C, resistance to disease; or D, more attractive flowers.
Again, I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answers are C and D.
Now Alex says, "I thought pollination was done by animals or the wind.
How can farmers control which flowers are pollinated by which?" What do you think? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
So artificial pollination can be done by hand to try and produce offspring with desired characteristics.
So this is pollination which is done by a human being by hand rather than an animal or nature producing and doing the pollination.
So this involves carefully moving pollen from one anther of one flower to the stigma of another using a tool such as a paintbrush.
And we've got a picture here showing what that looks like.
So this way a farmer can artificially pollinate an apple tree with very large juicy fruits with another apple tree that is very resistant to disease.
So here you've got two very desirable characteristics from two different plants and you are artificially pollinating them, which means that the new plant, the new apples, will hopefully be large, juicy fruits and also very resistant to disease.
So you're getting them both, which is fantastic.
So the offspring of these plants will have a combination of characteristics of each parent plant.
So they may both be resistant to disease and grow large and juicy apples.
So many of the beautiful and unusual varieties of orchids that can be bought today have been created through artificial pollination and selective breeding to give it those beautiful and unusual colours that you might not ordinarily have seen before.
So let's do a quick check-in of your learning before we continue.
It says, "How can farmers use selective breeding to produce offspring with desirable characteristics?" Is it A, artificial pollination by hand; B, animal pollination by insects; or C, automatic pollination by wind? I'll give you five seconds to think about your answer.
Off you go.
Fantastic.
Well done.
The answer is A, artificial pollination by hand.
Remember, you can use tools like a paintbrush for example.
So I want you to now have a go at your second activity and it says, "Imagine that you are a farmer.
I want you to choose two varieties of apple to artificially pollinate.
And then I want you to explain your choice." So choose two of these varieties of apples and explain your choice.
So you're going to have to write this down as well.
So I'd like you to pause the video here and have a go at doing that.
Fantastic.
Well done.
So Alex says, "I chose apples A and C because I hope that my new apple tree would have lots of large fruits like A and shiny, red fruit that grow quicker and are resistant to diseases like C.
Which one did you choose?" Well, let's have another look at them.
So if I was going to do this, I would go for, I think E looks like they're quite juicy, so I'd quite like E.
And I think C because it's resistant to disease.
So I would probably cross pollinate those two.
I'm sorry, artificially pollinate those two.
Did you have any other ideas? You might have gone for B and D or you might have even wanted to artificially pollinate two different colours.
Fantastic.
Well done.
So now's your second task of task B.
So it says, "Choose two varieties of orchid to artificially pollinate and draw what the offspring may look like." So you've got orchid A, orchid B, orchid C, and orchid D.
So you're gonna choose two of those and then you are going to artificially pollinate them and draw what you think the offspring might look like.
Okay, so I'd like you to pause the video here and have a go at doing that.
Off you go.
Fantastic.
Well done.
So Alex says, "I chose orchids A and D." and I can see that Alex has chosen kind of the spots, the pattern from orchid D, but chosen the colour from orchid A.
And I can see that he's also got the part where the stigma, the anther, where the pollen is, that is more closely linked to orchid D I think.
So Alex has done a really fantastic drawing of those.
Which ones did you choose? So if I was going to do this, I think I would go with orchid A and orchid B.
And I would use the colour from orchid B, but I would use the petal formations and the shape of the petals from orchid A.
I think that's what I would like if I was going to artificially pollinate mine.
But you may have chosen something different.
So now we are on to the summary of your learning today.
So pollination is when pollen from the anther of one flower is transferred to the stigma of another flower of the same species.
Plant offspring made with pollination will have a combination of characteristics of their two parent plants.
Selective breeding involves producing offspring from parents that have desirable characteristics.
It can be used to create plants that are more resistant to pests and disease, or those that grow better quality fruit and vegetables.
I am so proud of your fantastic work today.
You've done some brilliant explanations and some fantastic drawings.
And you've really used your critical thinking.
Well done.