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).
1 1. 2  Angiosperms, the Flowering PlantsIntroduction to AngiospermsThe flowering plants or angiosperms are included in the phylum Anthophyta.They are vascular plants which produce seeds contained in fruits that developfrom parts of reproductive structures called flowers. Theinner most series is the carpels, the female structures that produce the seeds.Carpels are often fused into a structure called the pistil.The seeds of angiosperms develop in an ovary, a part of the carpel thatsurrounds and protects egg-containing ovules.