The term "algae" refers to a class of mainly watery, photosynthetic, and nucleus-bearing organisms that lack the real roots, stems, and leaves of plants as well as their specialized multicellular reproductive structures.
Flagella are tiny, hair-like structures that aid in a cell's movement.
A cell is propelled through the liquid by the whip-like appearance of the flagella.
Few organisms use certain unique flagella as sensory organs that can detect changes in pH and temperature.
Even though some plant cells have flagella, the majority of them do not.
Most aquatic plants have flagella, which produces flagellated sperm that travels through the water to reach another plant's egg.
Most land plants do not have flagella since they do not need to move and do not require this mode of propulsion.
Some plants, like algae, bryophytes, pteridophytes, etc., produce flagellated male gametes.