What effects does Protista have on humans?

Protista are an important kingdom to all life on Earth.
Protists include algae. They produce most of the oxygen on Earth via the process of
photosynthesis. Besides that, the chemical energy that they produce is available to
primary consumers in ocean food chains. Without algae, there would be no ocean food
chains and all the fisheries in the world would die off. Protists make up the plankton
in the ocean that other organisms rely on as a source of nutrition. Some protists are
important as disease vectors. For example, amebic dysentery is a serious illness that
affects and kills humans. The protist Plasmodium falciparum causes malaria is a disease
that kills millions of people every year in the tropics and is carried by Anopheles
mosquitoes.