Wonder World Of Science : What Is In A Seed? (1989)

[Music] I wonder I wonder what do you wonder wondercat I wonder what's inside a seed what's inside a seed well if you're curious enough you can find out well I know that when you plant seeds you get Plants people plant seeds in their Gardens to get vegetables and flowers Farmers plant seeds to get all the plants that give us food so I guess I know that plants grow from seeds but how does that happen what's inside a seed Why not start by looking you could look inside this liab Bean a liab bean is really the seed of the liab bean plant now the seed is cut in half and opened up do you see anything there something's inside but it's awfully small wait I've got something that'll help help a magnifying glass now I can [Music] see it looks like a teeny tiny plant inside the seed is that really a plant there yes it is a baby plant are those really leaves on it yes they are and it has a stem and a root too but the baby plant inside the seed hasn't started growing yet and there's another important difference between this baby plant and plants that are growing the difference is in the leaves look at the leaves of this baby plant and compare them with the leaves of this plant can you see what the difference is well let's see this plant's leaves are a lot bigger and and they're green and inside the seed the leaves on the baby plant aren't green is that really an important difference yes you see the green material in a leaf which is called chlorophyll helps the plant make its own food plants need food yes all living things need food animals need food to grow and plants do too even a baby plant inside a seed but it doesn't have chlorophyll so it can't make its own food like other plants then where does its food come from look at the baby plant in the seed again what else is in the seed well there's stuff around the baby plant what's that that's the food you're looking for then that must be food in the other half of the seed so the baby plant does have food but if the baby plant has food right there in the seed with it why doesn't it start growing even before it's planted maybe what these children are going to do next will help you discover the answer they're watering the ground where the seeds were planted do seeds need water before the little plant plants inside them will start growing yes but that's not all the seeds need the weather has to be warm enough so that's why I couldn't plant my seed Outdoors when it was very cold but then what happens how do baby plants get bigger well that's something we can watch with special motion pictures that make plants seem to grow fast what we're seeing in a few seconds really takes several days to happen look at the lima bean seed you planted it's growing nicely look at that root coming out of the seed it's growing down and dividing into different [Music] parts the stem is growing up into the light and it's carrying the seed with it that's right that's the way of a bean plant grows and now look at those leaves coming out of the seed they're green that means it can make its own food and just in time too yes all the plants that are green have started making their own food what do they make their food out of several materials one is a gas that's in the air carbon dioxide carbon dioxide that's right carbon dioxide comes into the plant through its leaves the other material a green plant needs for making food is water I know where a plant gets that people water plants and it rains too yes that's right the water soaks into the soil so it goes down to where the plant's roots are then the water and certain minerals that are in the soil travel up through the plant's stem and all along its branches to the leaves and there the green plant makes its own food the plant uses this food and the minerals it gets from the soil to grow and in that way a young plant grows into a grownup plant your plant's been growing for about a month now I wish it grew as fast as those special movies you showed me but it's been growing well because it's been getting what it needs like the other plants here plants don't grow well if they don't get enough of what they need you mean if they don't get enough water for instance they'll grow slowly that's right but if plants get more of what they need they'll grow faster you mean more water yes but not too much and more sunlight and warmth yes but not too much and more carbon dioxide from the air and more minerals from the soil but not too much I know look at these plants they've really grown they must be getting just just the right amount of the things they need they are and mine is too oh look some of them have flowers yes but some flowers don't look the way we expect them to look these are actually flowers too the flowers of the oak tree trees have flowers Yes trees are plants and like many plants trees have flowers too those flowers are so small and they aren't colored very brightly you hardly notice them but some trees have flowers that look more like the flowers you're used to these flowers are on an apple tree apple blossoms are beautiful and so are orange blossoms many of the plants in the garden you and your friends planted have pretty flowers my little bean plant has flowers too they're small but they're pretty flowers are pretty but they also do an important job for plants what's that Stak curious and you'll find out changes are going to take place in the flowers but you'll have to wait a little while for them to happen I see the flowers are starting to change the flower petals look like they're drying up some are falling off yes they are but something else seems to be happening at the bottom of the flowers too that part is changing into something different yes it is apple blossoms are becoming apples and orange blossoms have started to become oranges flowers are changing into fruits that's right it's happening on the oak tree too the flowers are turning into acorns but acorns are nuts are nuts really fruits yes acorns are the fruits of the oak tree and on your plant the flowers are turning into bean pods but those are vegetables that's right you see some of the fruits of plants are what we call vegetables it will take a little time before all these fruits are ripe and then you will see what's special about the fruits of plants and now Weeks Later the apple tree is filled with ripe red apples let's look inside one of these [Music] apples seeds seeds are inside the apple and inside one of these oranges seeds are in inside the orange and the acorns and inside the acorn is that the seed of the oak tree yes it is and can you guess what will be inside the fruit of your bean plant bean seeds just like the one I planted I understand fruits come from flowers and seeds come from fruits and now I know what's inside each of those seeds a baby plant that will grow up and make its own seeds that have baby plants inside then they'll grow up to make wow that could go on forever I certainly hope it does me [Music] too