Chlorophyll Chlorosis can also be caused by pathogens including viruses, bacteria and fungal infections, or sap-sucking insects. Anthocyanins are other plant pigments. The absorbance pattern responsible for the red color of anthocyanins may be complementary to that of green chlorophyll in photosynthetically active tissues such as young "Quercus coccifera" leaves. It may protect the leaves from attacks by plant eaters that may be attracted by green color. The chlorophyll maps show milligrams of chlorophyll per cubic meter of seawater each month. Places where chlorophyll amounts were very low, indicating very low numbers of phytoplankton, are blue. Places where chlorophyll concentrations were
Chlorophyll a magnesium atom, and has several other attached side chains and a hydrocarbon tail. Chlorophyll "a" contains a magnesium ion encased in a large ring structure known as a chlorin. The chlorin ring is a heterocyclic compound derived from pyrrole. Four nitrogen atoms from the chlorin surround and bind the magnesium atom. The magnesium center uniquely defines the structure as a chlorophyll molecule. The porphyrin ring of bacteriochlorophyll is saturated, and lacking alternation of double and single bonds causing variation in absorption of light. Side chains are attached to the chlorin ring of the various chlorophyll molecules. Different side chains characterize