Q.Differentiate Homoiomerous and Heteromerous lichens.

Step 1. Recall the basis of this classification. Lichens can be classified by how the algal (phycobiont) cells are distributed inside the fungal (mycobiont) tissue of the thallus - this is a structural, anatomical way of grouping lichens, separate from classifying them by habitat or by outward thallus shape.

Step 2. Describe Homoiomerous lichens. In a homoiomerous lichen, the algal cells are distributed evenly throughout the whole thallus, mixed together with the fungal hyphae with no distinct internal layering - the thallus is structurally uniform ('homo-' = same, throughout).

Step 3. Describe Heteromerous lichens. In a heteromerous lichen, by contrast, the thallus is organised into distinct internal layers, and the algal cells are confined to just one of those layers (a separate algal zone), rather than being spread throughout ('hetero-' = different layers). …

Recall the algal-distribution basis of lichen classification and co …

• Confusing this classification (by algal distribution) with the separate classification of lichens by thallus shape (crustose/foliose/fruticose) or by habitat. …