hi I'm Jared welcome to fun science
demos today I'm surrounded by leaves
well these leaves if you look at them
tell a very interesting story take a
look do you have an idea of what story
they actually tell well where I live
most of the trees are going through this
interesting change their leaves most of
their leaves are changing from this nice
green to all of these different
wonderful colors reds and yellows and
oranges and browns and all of a mix in
between so the question I have is why do
those leaves change colors scientists
like to ask a lot of questions so let's
ask a question when do these leaves
start to change colors through science
we've discovered that these leaves start
to change colors when there's less hours
of sunlight during the day the amount of
sunlight during the day is what's key to
these leaves changing colors so why so
let's ask another question why is
sunlight so important to leaves well
through sites we've discovered that
there's a secret ingredient in these
leaves and that secret ingredient uses
sunlight to do some really amazing
things let's see if we can take a closer
look at that secret ingredient found in
leaves now through science we've
discovered that that secret ingredient
is only found in green leaves so to take
a closer look at that secret ingredient
I need some green leaves I need some
rubbing alcohol I need a paper towel and
I need a blender now we're gonna put
science to action
I'm gonna dump some rubbing alcohol into
the blender you can see that rubbing
alcohol is clear I can see right through
it next I need to take some leaves and
just tear them up into the blender the
blenders gonna do most of the work and
you can leave the stems out now I'm
ready to blend the leaves take a close
look and watch what happens to the clear
rubbing alcohol the blenders chopping
the leaves up into small little bits I'm
gonna stop the blender shortly so we can
take a closer look and see what's
happening so I finished blending my
leaves in my rubbing alcohol
take a look what do you notice I notice
that the green stuff in those leaves has
now colored the rubbing alcohol the
rubbing alcohol is now green that's a
lot of green stuff in those leaves to
take an even closer look at the secret
ingredient in green leaves we need to
pour the rubbing alcohol from the
blender to a cup we also need some paper
towel strips all I'm going to do is tear
the paper towel into little strips you
can cut them you can tear them
it doesn't matter now I'm ready to take
a closer look at the secret ingredient
in green leaves so what color do you see
in the cup well it obviously it's green
that secret ingredient in those green
leaves guess what it's green to take an
even closer look we need to take this
paper towel strip and we're gonna put it
in the cup put it right in the liquid I
like to bend the paper towel so it hangs
on the cup and what's going to happen
that rubbing alcohol with the green is
going to rise up through the paper towel
and we're gonna give it some time so I'm
holding two strips of paper towel that I
let sit overnight
I've also let them dry out let's zoom in
and take a closer look and really look
at what happened to our paper towel take
a look at our paper towel what do you
see well I see two colors I see green
but I also see yellow what does that
mean well that means that in my green
rubbing alcohol my green mixture there
must be some yellow color in there too
well why can't I see it
I can't see it because there's so much
of that green secret ingredient but when
I let it filter through the paper towel
the yellow comes out where have I seen
those two colors before green yellow
green yellow what's happening is that
green secret ingredient is in this leaf
and when that green secret ingredient
goes away the yellow is left behind so
all of these leaves used to have the
green secret ingredient but the tree
actually started to pull that green
secret ingredient back in so all of
these colors could show through now when
did that happen well the tree started
pulling that green secret ingredient
back in when there was less hours of
sunlight during the day so what is this
green secret ingredient and what does it
do with sunlight scientists call that
secret ingredient and leaves chlorophyll
and chlorophyll works with sunlight to
help make that tree grow and help make
that tree make food think about that all
the green stuff in this leaf that secret
ingredient is called chlorophyll and
that chlorophyll works with the sunlight
to give the tree energy to grow an
energy to make food now scientists have
a really neat name for that whole big
process it sounds scary but it's really
not when you break it apart scientists
call it photosynthesis photo means light
synthesis means to make the tree uses
light and chlorophyll to make food and
get energy that green secret ingredient
chlorophyll is so important that trees
want to draw it inside and save it when
there's not enough sunlight so when
there's not enough sunlight the green
stuff goes back into the tree the colors
show through and then they save that
green stuff inside for next year when
the tree can grow new leaves and get
more chlorophyll to work with the
sunlight to have more energy to grow
more food and the cycle goes on and on
round science is so cool if you want to
learn more check out our links in the
video description thanks for watching