Transcript Diapositiva 1

The journey of a
red blood cell
Hi there! Can you guess
what I am? I’ll give you a
hint… I have a very
important job inside your
body and your heart
helps me to do my job.
You are right!
That’s me. I’m a
red blood cell.
My job is so important that
you’ll thank me for it later!
But I can’t take all the
credit. Without your heart
I couldn´t do anything!
You see, I’m like a
little delivery truck in
your body.
I pick up and drop
things off all the time.
I ride the highways of
something called the
circulatory system.
I like to call it the
circle system because I
keep going in circles!
This system is made of
your heart and blood
vessels that carry your
blood to different areas
of your body.
Your blood vessels are
like tiny tunnels that run
all through your body.
They are made up of
arteries that take oxygen
to places in your body,
and veins that take
carbon dioxide from your
body to your lungs.
arteries
veins
But I can´t move by myself. I
move within your blood when
it moves. How does your blood
move? Your heart pumps it.
Let me show you how.
Your heart is the most
important muscle in your body.
It moves by itself and even
though you can hardly feel it,
it keeps moving all the time,
even when you are sleeping.
Do you want to feel
your heart moving?
Sit very still and put
your hand on your
chest.
If you were running hard
or doing exercise you
might find it easier to
feel.
When your heart moves
it
is
called
a
“heartbeat”. Your heart
makes at least 100.000
hearbeats everyday.
When your heart
beats it pulls
blood into it and
pushes
it
out
again.
This helps the blood to
move fast enough to go
through your whole body
and back. An it helps me
to pick up my deliveries
and take them to
different places in your
body.
I’m not alone. There are
lots of red blood cells
just like me doing the
same thing in your body
all the time. Even now,
while I’m talking to you!.
Going
through
the
heart is easy because
it has special rooms
and doors that only
open one way.
Here’s me at the
start of my little
journey. I just got
back from dropping
off some things to
some places in your
body.
I need to get some
more speed to do
more deliveries so I
ride your bloodstream
into your heart.
Right now I ‘m
entering the right
side of the heart
through the superior
and inferior
vena
cava.
I go through the first
room called the “right
atrium”, through the first
door called the “tricuspid
valve” and through the
second room called the
“right
ventricle”
and
through the second door
called the pulmonary valve.
The heartbeat causes the
heart to squeeze the
blood on these rooms into
the next area.
It pushes the blood
through it and into the
arteries (like tunnels)
that lead to other parts
of the body. I go out of
the heart through the
pulmonary artery.
So, now I’m moving a little
faster because the heart
has given me push.
Now I need to go and pick
up the things I need to
deliver.
My first stop is to the
lungs. I need to pick up a
little oxygen molecule to
take to some place in the
body.
Everybody needs oxygen.
Our lungs bring it into our
body, and then I pick it up
and take it to where it is
needed.
inhalation
It seems like it would be
tricky to pick up the
oxygen, but the lungs really
help me with that job.
Here in the body we all
work together and cooperate to keep everything
running smoothly.
When I get to the lungs
and I get really close to
the sides of my little
tunnel … the oxygen that
is sort of floating out of
the walls nearby just
jumps onto me for the
ride.
While this is happening I
also make another change.
Carbon dioxide needs to
be taken up to the lungs
so that the body can get
rid of it by breathing out.
And I’m just the cell to
do it!
When enough of oxygen
has hopped on and I
can’t hold any more I am
ready to go back to the
heart for another push.
This time I need to go in the
other side of the heart. This
side is for all of us, red blood
cells that are carrying
oxygen. I enter the heart
through the pulmonary veins.
I go through the first
room called the “left
atrium” through the
“mitral valve” and into
the
“left
ventricle”
room to get my big push.
The heart pushes us a
little farther this time
because some of us have a
very long trip. We leave
the left side through the
aorta artery.
I like my job
because I get
to travel.
So that is my job! What
do you think? Pretty
important, isn’t it? The
heart really helps me to
do my job well!