The major difference between angiosperms and gymnosperms comes from the .

production of microspores versus megaspores
presence or absence of alternation of generations
presence or absence of vascular structures
dominance or lack of dominance of the sporophyte generation
presence or absence of a protective covering over the ovule

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.

Number and variety of living organism; includes genetic, species, and ecological types

Eutrophication caused by human nutrient pollution.