Causes. Sunburn results when the amount of exposure to the sun or other ultraviolet light source exceeds the ability of the melanin to protect the skin. Melanin is the skin's protective coloring (pigment).kin cancer usually appears in adulthood. But it is caused by sun exposure and sunburns that began as early as childhood. You can help prevent skin cancer by protecting your skin and your children's skin from the harmful rays of the sun.
The angiosperms, or flowering plants, are one of the major groups of extant seed plants and arguably the most diverse major extant plant group on the planet, with at least 260,000 living species classified in 453 families (Judd et al., 2002; APG II, 2003; Soltis et al., 2005).
(botany) A flowering, fruit-bearing plant or tree known for having ovules (and therefore seeds) develop within an enclosed ovary. Supplement. Angiosperms are plants producing flowers.Thus, they are also commonly called as the flowering plants.They belong to the Kingdom Plantae, Subkingdom Embryophyta. They have closed carpel enclosing the ovules. 2  The carpel (s) and other accessory parts may develop into a fruit, which is an important plant organ for seed dispersal. 3  They form endosperm, which is a nutritive tissue for the developing embryo or for the seedling.