$P_{700}$ is a special form of which pigment?

Which property of the pigment is responsible for its ability to initiate the process of photosynthesis? Why is the rate of photosynthesis higher in the red and blue regions of the spectrum of light?

Match the following columns:

Column-$I$ (Pigments)	Column-$II$ (Color)
$P$. Chlorophyll $a$	$I$. Yellow-orange
$Q$. Chlorophyll $b$	$II$. Yellow-green
$R$. Carotenoids	$III$. Bright or blue-green
$S$. Xanthophylls	$IV$. Yellow

If chlorophyll is burnt,which element will be left as the residue?

How many chlorophyll molecules combine to form quantasomes?

Which element is present in the center of the porphyrin ring of chlorophyll?