In the United States, the parasite that causes malaria is not present, but African-Americans whose ancestors were from equatorial Africa are present. What should be happening to the sickle-cell allele in the United States, and what should be happening to it in equatorial Africa?

Muriel is an 86-year-old woman who tries to function independently but has suffered for several years with forgetfulness, especially with recent memories. she has trouble recalling the names of her best friends when they call on the phone, and she worries that she may have a form of dementia called alzheimer's disease huntington's disease schizophrenia parkinson's disease