Many different types of mutations can occur within the body. sickle cell anemia is a disease that occurs when a mutation in a base pair of the hemoglobin beta gene causes a single replacement of the amino acid glutamic acid by the amino acid valine. as a result of this mutation, the individual’s blood cells take on a sickle shape under certain conditions and form clusters that can block blood vessels and cause organ damage. mc017-1.jpg mc017-2.jpg which type of mutation causes sickle cell anemia?

Sediment layers stop lateral spreading when: they encounter a barrier they encounter an opposing current they run out of additional sedimentary material

Hydrilla (hydrilla verticillata) is an invasive aquatic plant and one of the most serious aquatic pests in florida. hydrilla has already been introduced to hundreds of bodies of water throughout florida, hydrilla is difficult to control because it grows rapidly and survives in many different water depths and conditions. hydrilla • describe how hydrilla affects native plant and animal species. include both a biotic and an abiotic limiting factor. • suggest one biotic and one abiotic recommendation that could slow the spread of hydrilla

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of