In, 1898 the Russian cytologist S. G. Navashin discovered double fertilization in angiosperms, which consists in the union of a sperm-ucleus with an egg cell nucleus and the union of a second sperm nucleus with the nucleus of an endosperm-producing cell.
Bioculture is the combination of biological and cultural factors that affect human behavior. Bioculture is an area of study bounded by the medical sciences, social sciences, landscape ecology, cultural anthropology, biotechnology, disability studies, the humanities, and the economic and global environment.
A biome comprises the community of plants and animals that exist under climate conditions. Freshwater biomes have suffered mostly from pollution. Runoffs containing fertilizer and other wastes and industrial dumping's enter into rivers, ponds and lakes tend to promote abnormally rapid algae growth. When these algae die, dead organic matter accumulates in the water.