Which of the following is true of sickle-cell anemia?
A) It is on the decline.
B) It is caused by the change in two amino acids that make up the hemoglobin molecule.
C) It results when hemoglobin molecules do not fold correctly, reducing their ability to bind to oxygen.
D) It increases an individual's susceptibility to malaria.

Question

Quizplus · Accepted Answer

Sickle-cell anemia is caused by a mutation in the hemoglobin gene that leads to the incorrect folding of the hemoglobin protein, which in turn reduces its ability to carry oxygen efficiently. This mutation affects only one amino acid in the hemoglobin molecule, not two, making option B incorrect. Contrary to increasing susceptibility to malaria, the sickle-cell trait provides some protection against malaria, making D incorrect. The prevalence of sickle-cell anemia is not necessarily on a global decline (A), as its occurrence is closely linked to geographical regions and genetic backgrounds.

Which of the Following Is True of Sickle-Cell Anemia