Hello and welcome to fun science demos recommends. my name is Dr. Mehler, and along with jared and
our team, we produce fun science demos, the youtube channel to learn science the fun way.
this playlist, fun science demos recommends, will recommend the best free learning tools
for you to learn science - and they are from all over the world. we place the link for you
to go directly to the learning tool in the video description. please tell us what you
like about the learning tool and subscribe to our channel for new science demos all the time.
so one of the really cool things about science is that we can learn lots of different things about
life, and all living things on our planet are made up of cells and what this learning tool does is
it helps us get a sense of how small these cells really are. almost all cells can only be seen with
a microscope. a microscope is a special instrument that allows us to see things that are much
much smaller than we can see with our eyes. so let us take a look at this interactive from the
university of utah, a wonderful interactive that comes from a great website. it is trying to give
you a sense of how small cells are. we supply the link so that you can go directly to this
in the video description. okay so many of us know how big a millimeter is, so right here
we have on our scale one millimeter. so the distance from here to here is one millimeter, and
if a millimeter is that big, a coffee bean would be this big. a grain of rice would be this big,
a sesame seed would be this big. so what we are going to do is we are going to take the slider
down here and we are going to start moving it, and we start zooming in very very slowly. there
is our sesame seed which is about three by two millimeters. there is a grain of salt,
which is less than a half millimeter, but look what is happening to our scale. up here
pretty soon we are going to be so small that we can not use a millimeter anymore. we start using
a unit called microns or micrometers. we take one millimeter we divide it by a thousand and that is
a micron. so let us keep going down. now we are in microns. here is an amoebis proteus which is
a large one-celled organism which is about 500 micrometers, or about half of a millimeter,
and we keep going down, down, down. there is a human egg at 130 microns. there is a human sperm,
much smaller, and the skin cells similar to what might be inside your cheek is here at 30 microns.
so let us keep going, so cells are about this big. here is a red blood cell which is about
eight microns big, but now we are leaving the world of cells, and we are going down to parts
of the cells like a mitochondria, or a cell that is much smaller than our cells. this is a bacteria
cell. now we can continue to zoom down here, but i am not going to do it. i want you to see
what you can find out, so i am going to come back - now i am going to zoom out and i am
going to invite you to go to that description and see if you can figure out what would be even
smaller than our cells. this is a wonderful interactive and we will link to it. we also
have a place where you can read about cells if you would like to read about cells, on a free textbook
that we have also linked to. so remember this is funsciencedemos recommends. we recommend all
sorts of learning tools in our playlist. do not forget to subscribe to funsciencedemos. we have
new science demonstrations all the time. thanks for listening, and good luck learning science.
just a quick note: we are going to put this link in our description right here, and what we just
showed you was cell size and scale. click here for this interactive to explore but as you can see
from this wonderful site from the university of utah learn.genetics.utah, there are tons more here
where if you want to learn anything about life science, this is a wonderful website to explore.