With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: A block is rarely called a "denial."
text_B: Cyanolichens are lichens that contain cyanobacteria , otherwise known as blue-green algae .. cyanobacteria. cyanobacteria. algae. algae. green algae. green algae. Some lichens contain both green algae and cyanobacteria .. cyanobacteria. cyanobacteria. algae. algae. green algae. green algae. In these cases , the cyanobacteria may be enclosed in cephalodia .. cyanobacteria. cyanobacteria. cephalodia. Cephalodium. These outgrowths of the main thallus can take many forms .. thallus. thallus. The cyanobacteria which live in cephalodia can function in nitrogen fixation on behalf of the lichen .. lichen. lichen. cyanobacteria. cyanobacteria. cephalodia. Cephalodium. nitrogen fixation. nitrogen fixation. These cyanobacteria are generally more rich in nitrogen-fixing cells called heterocysts than those cyanobacteria which may live in the main thalli of lichens .. cyanobacteria. cyanobacteria
not_related.