Evening star., 1940-12-19
Of Stors, Men
And Atoms
Notebook Of Science Progress
In Field. Laboratory.
And Study
BIZ Thomas r. Henrv.

By Thomas r. Henry.
A partnership of light and darkness In
the basic mechanism Of all life on earth
has just been uncovered by biologists Of
the Carnegie Institution Of Washington.
From the soil green plants absorb
water through their roots. Through
their leaves they breathe" out Of the
air the gas carbon dioxide which con-
stitutes q minute amount Of the earth's
atmosphere. Through the molecules Of
chlorophyn, the green coloring matter
In leaves, they trap sunshine. They
use the energy Of this sunshine 70 split
the carbon dioxide into carbon and
oxygen. The oxygen is released into
the air where animals can breathe 1t.
Otherwise all animal life would quickly
smother to death. They combine the
carbon with hydrogen from the water
to form sugars, starches and other COM
pounds which are the basic foods Of
dl1uI04os ~ oAAC1lSC OOuAo OupA4SdVV CAlAo
process. 1t would be first step toward
test-tube life.
Last year radioactive carbon dioxide
was produced by Carnegie physicists.
The carbon atoms in this synthetic gas
exploded every few seconds. It is proving
perhaps the most potent tool ever found
for looking into the fundamental mys-
teries of life. A plant can be put in an
atmosphere of exploding carbon dioxide
and each step of the gas in the chemical
laboratory of the leaf followed minute
by minute. Thus far the experiments
have been conducted with sunflower
leaves.
1t has already been demonstrated by
this method according to report by
DR.. H. A. Spoehr, head of the Division
of Plant Biology, that the constantly
breathing leaf fills up a carbon dioxide
reservoir during the darkness Nature
has provided three processes for filling
this reservoir. Some of the carbon
dioxide is dissolved in the water of the
sap, thus constituting sort of primeval
fzz water. Some is combined with
carbon combinations previously built up
in the plant, and some is actually COM
bined in organic compounds.
The reservoir then is ready for the SUM-
light to be turned on. It is as if the
leaf had night force of workers getting
everything ready for the day workers.
All these reactions. DR.. Spoehr says,
occur in the dark. The fact that the
carbon dioxide absorbed in the dark can
be converted into organic material by
illumination indicates that the absorp-
ton of carbon dioxide is independent Of
the photochemical reaction.
The exploding carbon dioxide now
used has very short life. Carnegie
physicists are working on a long-hfe
radioactive gas which will make it pos
sible to follow the basic process Of life
through several days, or even weeks.
At the same time, DR.. Spoehr an
nounced. another new tool has been
found in the form of albino cornstalks
fed with sugar. Is there one parent SUBJ
stance of plant life formed by the COM
bination of hydrogen and carbon in the
photosynthetic process? In any actual
plant, DR.. Spoehr says, there are an
enormous number Of chemical products
fats, proteins, drugs, rubber, pigments,
hbers. Various other elements, such as
nitrogen, are combined with the carbon
and hydrogen.
It may be, he says, that sunlight pro-
duces one simple hydrocarbon from
which all the other products are formed
by other chemical processes, or that the
majority of them are the direct result
of ptotosynthesis itself. Now an albino
plant has no chlorophyll and hence can
trap NO sunshine. Usually it starves to
death in few days, as soon as the
minute amounts of food stored in the
seed have been exhausted.
During the past year, DR.. Spoehr an
nounced, a means of artificial feeding
has been devised by which it is possible
to keep such plants alive for at least
four months. They are fed on q solu-
ton of cane sugar. When they die they
are subjected to minute chemical analy-
sis to determine just what they have
been able to make out of the sugar
itself a carbohydrate perhaps roughly
similar to the supposed parent product
formed by sunlight.
From the results to date it has been
determined that such plants are able to
transform the sugar they eat into some
of the structural materials of the corn
stalk, but less efficiently than by the
sunlight process. They are being tested
for the presence Of hormones and vita
minis which are produced In abundance
by normal plants.
They also are studying the engines
produced in plants. It has been de-
termined that pigments isolated from
leaves differ in certain vital respects
from those in the living plant. This
forms hurdle which the biologists have
not yet bee1 able to cross.
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