Question

a filamentous alga is called​

Answer 1

Answer:

Filamentous also known as "pond moss" or "pond scum" these threadlike algae often occur in huge greenish masses floating upon the waters' surface. They can form dense mats in static water or long, rope-like strands in flowing water.

Answer 2

Answer:

“moss” or “pond scum”

Explanation:

Filamentous Algae - Filamentous (green) algae, often called “moss” or “pond scum,” are characterized by long, hair-like strands, or filaments, of attached cells (often reaching two metres in length).

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