Question

Algae are not associated with diseases unlike many fungi and bacteria. What is the reason for this?

Answer 1

Pathogenicity occurs due to a certain mode of nutrition followed by reproduction, wherein an organism acquires it food and then undergoes replication or reproduction by infecting the cells of another living organism, the host, however, this results in a diseased condition for the host. Since, algae are photosynthetic autotrophs they are capable of preparing their own food, unlike many fungi and bacteria that lack the necessary pigments for autotrophic mode of nutrition and hence are saprophytes or pathogens.