Page 126 - Miracles Within the Molecule

HArun yahya

The Molecules That Let You See

Molecules in your eyes again per ceive mol e cu les. Molecules are
respon si ble for the color we per ceive in objects, and at the same time,
mol e cu les in our eyes react to the light enter ing from out side.
Many nat u ral col ors form as a result of spe cial mol e cu les that give
rise to them. Trees in the street and the flow ers in gar dens owe their col -
ors to these mol e cu les. These mol e cu les are also respon si ble for the color
of your skin, hair and eyes.
Before we exam ine the mol e cu les that give rise to—and respond
to—col ors, recall the kind of activ i ty involved in see ing. The ret i na con -
tains two types of recep tor cell: rods and cones. The 1 bil lion or so rod
cells per ceive dark er shades of light, but do not dis tin guish col ors. The
3 bil lion or more cone cells per ceive bright light and do dis tin guish col -
ors. Every recep tor cell con tains light-sen si tive mol e cu les, and their
reac tions to light deter mine the mes sage sent to the brain.
The ret i na's mol e cu les that make sight pos si ble are hydro car bon
groups, bond ed in a spe cial way. The bonds that give rise to these mol -
e cu les are inflex i ble, mak ing the chain rath er strong. The sec ond impor -

Nerve
fibers
trans port -
ing vis u al
data
Regions
con tain ing
pig ment
Nerve
cells
Binding
nerve cell
layer

Cone Rod cell
Rod and cone cells. (The white cell
arrows indi cate the light-sen si tive
areas of the rod and cone cells.)
The ret i nal mol e cule that per mits the vision proc ess is a hydro car bon group, bond ed in a spe -
cial way. The bond is inflex i ble, and the elec trons in the chain are loose ly attached to one
anoth er. Able to move with ease, these elec trons can absorb ener gy from the light fall ing onto
the mol e cule.

124