Page 96 - Photosynthesis: The Green Miracle

Adnan Oktar

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dependently. Bearing in mind that human
beings have communications and deci-
sion-making mechanisms for systems of
this kind, the astonishing nature of what
an ordinary cell does, not being con-
trolled from any one single place, can be

better understood.
The oxygen manufactured as a byprod-
uct during photosynthesis can be emitted
by the leaf only through an open stoma.
Considerable water loss is also experienced
during this exchange of gasses. The stomas
that cover 1% of the leaf surface are re-
sponsible for 90% of the water it loses. On hot days, cotton plants, for ex-
ample, lose around 400 liters of water an hour. Other environmental fac-

tors also affect the stomas’ opening and closing. When the water level in
the leaf drops below the critical point, the stoma closes in order to prevent
the remaining water from evaporating. When the guard cells controlling
the stoma absorb potassium ions, water enters the cells and causes them
to swell, and thus the stoma opens. When potassium leaves the cell, wa-
ter again leaves the cell and the stoma closes. This system is regulated and
directed by a hormone known as abscisic acid, depending on the level of

water in the leaf. 34
Although most plants have stoma that open in the daytime and close
at night, those of some species —such as cacti or pineapple that live in hot,
dry climates—close in the daytime and open at night. These plants absorb
carbon dioxide at night and transform it into 4-carbon acid. In the day-
time, when the stomata are closed, carbon dioxide exits the acid and is im-
mediately used in photosynthesis. This process is known as crassulacean
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acid metabolism, and such plants are called “CAM plants.” When only the
stoma between the leaf sections are examined, an amazing design can be

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