Yes it does. (but not always) Algae is not technically a plant it is a protista, Algae reproduce by using little spores or by growing copies of themselves from broken fragments and do not have specialised reproductive structures like all other plants. If the spores are created using just one plant it is asexual. If spores are created when two (one female, one male) algae fuse it is sexual. And lastly when it reproduces by growing copies of itself it is called vegetative reproduction.
They reproduce by cell splitting but can also reproduce in other ways too.
Asexually
Red algae reproduces through asexual reproduction into a number of single-celled stages called spores.
Algae is a micorscopic plantlike organism, it makes itself.
Alate is able to reproduce in the gametophyte phase
Brown algae
Quaggas cannot reproduce faster because there are so few left.
Alate is able to reproduce in the gametophyte phase
Alate is able to reproduce in the gametophyte phase
Copepods reproduce by spawning, like most aquatic animals. They do not need much light to reproduce, but need plenty algae to survive.
Algae reproduce by means of spores. The oceans are always releasing these spore into the air, and any exposed water is going to have spores fall into it, which can then grow into algae, as long as there is sunlight and some mineral content to provide the algae with the necessary ingredients for growth.