circulation of the blood and the optical nerve

1. Circulation of blood and
the optical nerve
Biology Experiment
Etwinning project Belgium-Italy

2. Done by:
ALBERTO ROSSI
17, ITALY
AUDE SPIESSENS
14, BELGIUM
JANA VANLUCHENE
14, BELGIUM

3. Our Experiment:
We had to see how the circulation of the blood influences the optic
nerve, when you are into the space, and what it produces.
To do this experiment we just need a tape measure and someone
who can be measured.

4. What to do?
We had to easure the periphery of our neck and ankles while
we were standing up straight. Then we have done the same
while we were laying down.
As last step we have measured our ankles and neck while
standing upside down. Our results are in the next slide...

5. CIRCUMFERENCE STANDING UP LAYING DOWN UPSIDE DOWN
Neck (cm) 38 40.5 42
Ankles (cm) 24 23.5 23
Italian results:
Belgian results:
CIRCUMFERENCE STANDING UP LAYING DOWN UPSIDE DOWN
Neck (cm) 31 33 37
Ankles (cm) 21 20 18
Our Results:

6. Comparisons:
As we can see in the previous slide,
the data are different, but the
variation of lenght is constant in both
the tables. That’s because on the
Earth the gravity force is everywhere
the same: 9,81 m/s2 ,it doesn't
change. The data in the two tables
are different because, of course, the
person who has been measured is
not the same.

7. Conclusions:
In space, in absence of gravity, the blood is spread equally all over
the body; for this reason, the pressure of the blood around the brain is
transmitted along the optical nerve into the eye and it increases the
pressure of the eye, causing the view of flashes of light. In addiction,
the flashes can also be produced by cosmic rays.
Otherwise, on the Earth the circulation of blood behaves in a different
way because of the gravity. In fact, while standing up, the blood is
attracted to the middle of the Earth, it is more concentrated in the
ankles than in the neck.
Instead, while laying down, the blood spreads all over the body, so,
the measure of the circumference of the neck increases while the
circumference of the ankles decreases.