Crosswords Solver

Answer: porphyrins
Answer	Crossword Clue
porphyrins	Any of a class of pigments (including heme and chlorophyll) whose molecules contain a flat ring of four linked heterocyclic groups, sometimes with a central metal atom
porphyrins	PORPHYRIN, any of a large group of red or purple crystalline pigments present in plant and animal tissues

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.

Answer: porphyrins