Question

Sickled red blood cells carry less oxygen than normal red blood cells. What does this demonstrate about mutations in the DNA that codes for hemoglobin?
A.
These mutations are unable to affect the structure and function of hemoglobin.
B.
These mutations decrease the amount of oxygen available to bind with hemoglobin.
C.
These mutations can change the structure and function of hemoglobin.
D.
These mutations can change the structure of oxygen so that it does not bind to hemoglobin.

Answer 1

C.

A point mutation in the hemoglobin gene (e.g., Glu → Val in β‑globin) alters the amino acid sequence, changing hemoglobin's structure and therefore its function (reduced O2‑carrying capacity and polymerization that causes sickling).