Question

The following question has two parts. First, answer Part A. Then, answer Part B.Caused by a mutation, sickle cell anemia is a disorder that affects hemoglobin, the red blood cell molecule that carries oxygen to cells throughout the body. The β chain of the hemoglobin protein is a single chain of amino acids and is 147 amino acids long. In humans, the gene that encodes for the β chain is located on chromosome 11. The diagrams show the DNA, RNA, and amino acid sequence of an unaffected person and a person with sickle cell anemia.image f8707eaefc0147c9bd074a15bb19c344Part A:Where does the mutation that causes this disorder occur?AThe mutation occurs on the DNA.BThe mutation occurs on the RNA.CThe mutation occurs on the ribosomes.DThe mutation occurs on the amino acid.Part B:Which BEST describes the result of this mutation?AThe entire sequence of amino acids is changed.BThe RNA strand does not code for the correct amino acids.CThe change in amino acids shortens the polypeptide sequence.DThe alternation of a single nucleotide encodes for a different amino acid.

Answer 1

Sickle cell disease is a hereditary disease seen most often among people of African ancestry. Caused by mutations in one of the genes that encode the hemoglobin protein, the disease is inherited as an autosomal recessive trait. The mutation causes the red blood cells to take on an unusual sickle shape. Individuals affected by sickle cell disease are chronically anemic and experience significant damage to their heart, lungs, and kidneys.