60 | SCIENCE ILLUSTRATED
establish a huge store for the benefit of science. “Biological
banks with blood, urine, and amniotic fluid already exist. We
want to make one with tears, so scientists’ research will take
two weeks instead of six months,” Sobel says to the Scientific
American magazine. Sobel intends to build his tear bank at
the Weizmann Institute of Sciences in Rehovot south of Tel
Aviv, where he heads the neurobiological research unit.
In the new biological bank, tears are to be separated and
divided into types. One section will
include tears from men, whereas
women’s tears will be kept in a
different place, because research
has shown that the tears of the two
sexes are chemically different.
Tears from people in grief will also
be separated from the ones
produced as we chop onions or get
a fly in the eye.
Scientists generally divide
people’s tears into three categories:
basal tears, reflex tears, and
emotional tears. Basal tears
moisten, cleanse, and protect our
eyes. They are produced all day long in small tear glands over
both eyes. Every day, an average human secretes about 1 mm
of basal tears,which primarily consist of salts and nutrients
for the cells on the surface of the eye. Moreover, they include
important antibodies and proteins,which combat bacteria,
viruses, and fungi, i.e. they prevent eye inflammation from
blurring our vision. The production of basal tears slowly
decreases with age, and so, many people experience that
their eyes become irritated and blurred, when they grow older.
The second type, reflex tears, are produced, when you
chop onions or the like. As the knife cuts, enzymes are
released to irritate the eye and stimulate the tear glands to
secrete extra fluid in the shape of reflex tears which wash
away the enzymes. Dust, chemical vapours, or retina ulcers
also cause reflex tears which include extra quantities of the
proteins and enzymes that kill bacteria. Reflex tears also
include growth materials which boost cell
formation, healing eye ulcers.TEARS EASE PAIN
The third type of tears, emotional
tears, are the most mysterious.
Humans are the only known
species to cry to comes to
terms with extreme grief,
sudden happiness, or
other very intense
emotions, and
scientists have tried
to find out why for
years. They know
that emotional tears
include pain-relieving
hormones which do
not exist in the two
other types of tears,An Israeli scientist has invented
a method for freezing tears,
so he can store them without
breaking them down.
Biological
banks with
blood, urine, and amniotic
fl uid already exist. We want
to make one with tears.NOAM SOBEL
BRAIN RESEARCHER, TEL AVIVEMOTIONAL TEARS
INCLUDE MORE
PROTEIN THAN
OTHER TEARS.T
he midwife is relieved when she hears the
newborn baby in her arms cry. The baby girl's
crying tells her that the kid's circulation is
working the way it should. The midwife feels
tears of relief in her eyes. In a corner of the room,
she can see the new father. His eyes get wet, when he sees
his daughter for the first time. The mother is still lying down,
her face wet with all the tears she cried out of pain, as she
was giving birth. Now, tears of joy are
rolling down her cheeks.
Crying is one of the few things we
master at birth, and even after we
have learned to speak and express
ourselves in other ways, most of us
also cry as adults. Nevertheless, we
know very little about why we cry,
but Israeli scientist Noam Sobel
intends to change that.
Noam Sobel aims to find out why
we cry by taking a close look at our
tears. For many years, he has been
trying to map out the salty drops,
each of which includes billions of
molecules. With the new tear bank, scientists will not only be
able to find the exact chemical make-up of our emotional and
basal tears, they can also find inspiration for new drugs and
spot severe illness, before it breaks out.BANK TO SEPARATE FEMALE AND MALE TEARS
Every time Sobel makes a new tear experiment, he
encounters the same problem: lack of tears. So, he intends toMAURICE MIKKERS/MICROGRAPHSTORIES.COM
HUMANS THE HUMAN BODY