WEBVTT

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[MUSIC PLAYING]

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For this flower dissection,
we're using a lily

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because it's a really large flower
that's got really obvious and very

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distinct reproductive parts.

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Now the first thing
that we're going to do

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is remove this outer layer here.

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These are the parts
known as the sepals.

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And you can see there,
they are the first thing

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that comes out at the top
of the stem of the flower.

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[MUSIC PLAYING]

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We can see here on
this diagram, there

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is the stem, the
receptacle at the top.

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And the sepals are sticking out
either side, and they're in green.

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The petals are above
them, and they're brightly

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colored to attract insects.

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Here you can see the sepals are
green on the bud of the flower.

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But in the earlier stages
of it starting to bloom,

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they are the same
color as the petals.

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So in this particular species,
the petals and the sepals

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look almost identical.

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Now that we've removed
a few sepals and petals,

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we can see much more clearly what's
on the inside of this flower.

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And you can see on
this one that we've

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got both the male and the
female reproductive parts,

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which have been produced at once.

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At the base of the
petals here, we've

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got this sticky sugar-containing
fluid, and this is known as nectar.

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And it's there to
attract insects, which

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are necessary for pollination.

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Let's take a closer look now
at the male reproductive part

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of the flower.

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This part is known as the stamen.

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And the stamen contains the anther,
supported by a stringy thing called

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the filament.

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The job of the anthers
is to produce pollen.

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The anthers produce the
male gametes of the flower.

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In the earlier stages of
blooming of the flower,

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you can see the pollen starting
to burst out of the anthers.

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But once the flower's
more mature, they're

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a lot more exposed and readily
released from the anthers.

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And you can see these coming
off here as a sort of dust.

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We can put this onto
a microscope slide,

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and then put it under the lens to
have a little closer look at it.

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And you'll be able to see the
individual pollen grains that have

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been released from the anthers.

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Next, let's have a look at
the female reproductive part

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of the flower.

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At the bottom here is the ovary.

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This is the slightly large,
inflated part, which will

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go on to develop into the fruit.

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Above that is the style.

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And at the top of the
style here is the stigma.

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And this is where
the pollen must land.

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In the diagram here, you can see the
carpel with the ovary at the bottom

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and the style above it
and the stigma on top.

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This is the female
part of the flower.

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And inside of the
ovary are the ovules.

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Here we've got the female gametes.

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We can now cut into
the ovary so that we

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can get a little bit of
a closer look of what

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this looks like on the inside.

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[MUSIC PLAYING]

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We've cut off the outer layer.

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And now we'll cut off
a little section of it

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so that we can have a closer look.

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[MUSIC PLAYING]

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On the inside of
the ovary, we've got

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lots and lots and lots of these
absolutely tiny, little ovules.

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We really need to see
them under a microscope

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to get a good view of them.

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So that's the entire
structure of the flower,

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with the sepals coming out of
the receptacle at the base,

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the petals above them, which are
there to attract insects, which

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is why they're brightly colored.

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The female system is
known as the carpel, which

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contains the ovary at the
bottom with ovules inside of it,

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the style above that, and
the stigma at the top.

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And the stigma is the place
that receives the pollen.

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The male part is known
as the stamen, which

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consists of anthers at the top of
it and the filament beneath it,

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supporting it.

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[MUSIC PLAYING]