The pigments have a similar
structure of 40 carbon atoms covalently bonded in a chain. Carotenoids contain oxygen atoms in their chemical structure (retinyl functional group) while
xanthophyll does not. This makes carotenoids more non-polar compared to xanthophylls,
hence move farthest in chromatography
paper using a nonpolar mobile phase. Chlorophyll
pigment, on the other hand, has chlorin rings (which are larger) as functional
units hence move slowly in chromatography.
Photosynthetic rates
can be measured by either the amount of
oxygen they consume per particular time period
or the amount of carbon dioxide produced per particular time period. This
is conducted while immersed in water so
as to measure bubble rate formation in case of oxygen production or the change
in water pH in the case of carbon dioxide consumption.
When autumn approaches, the amount
sunlight received by the plant is reduced due to longer night than days. Deciduous trees have adapted by losing
chlorophyll a and b pigments (most important in photosynthesis)
during this time. This leaves a higher amount of the other red and yellow pigments hence making the leaves change from
green to yellow-red.
It is believed that this
is the result of an ancient endosymbiotic
relationship between a protist and a
eukaryotic cell. The protist generates energy
that the eukaryotic can utilize in its growth and reproduction while
the protist is sheltered. This relationship became obligatory symbiosis over
time.
