Page 136 - Photosynthesis: The Green Miracle

Adnan Oktar

have short life spans. Were it not for this annual loss of chlorophyll, the
consequences would be disastrous. Increasing levels of chlorophyll would
lead to seaweeds and algae cells able to use less sunlight. As a result, cells
would receive insufficient quantities of light, resulting in less photosyn-
thesis. Life would come to an end in the oceans, and thus in the whole
world.

One of the most interesting phenomena that take place in leaves
about to be shed is the exceedingly purposeful break-down/separation
process. Before the leaf falls, useable substances such as protein and car-
bohydrate are stored in the branches or stems of the plant. Thus the leaf
that is due to fall does not take these substances with it, and an important
part of the materials necessary to form leaves in the future is retained. As
can be seen from these examples, it is ecologically essential for the surviv-
al of life on Earth for chlorophyll to be eliminated at the correct time and
for the substances a plant needs to be stored inside while it goes dormant.

One of the first signs of aging in leaves is that the cells in the base of the
leaves beginning to produce the gas ethylene. Shortly afterwards, the eth-
ylene spreads to all parts of the leaf, and when it reaches the leaf stalk,
small cells where the leaf stem joins to the main body of the plant, the
small cells here begin to swell up, leading to a tension in the stem. The
number of cells in the section where the leaf is bound to the stem raises
and they begin to produce special enzymes. First of all, cellulose enzymes

break down membranes consisting of cellulose, then pectinase enzymes
break down the pectin layer that binds the cells together. The leaf becomes
unable to withstand this increasing weakness, and the stalk starts to sep-
arate from the body of the plant.
Long before the leaf falls, a detachment zone forms where the leaf
stem joins the main body. The membranes of special impermeable tissue
cells known as the parenchyma begin to soften and assume a jelly-like
state by passing through various chemical changes. This causes the cells
to divide from one another. The leaf is soon joined to the plant’s main

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