Normal hemoglobin is a tetramer, consisting of two molecules of β hemoglobin and two molecules of α hemoglobin. In sickle-cell disease, as a result of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assemble into large fibers. Based on this information alone, we can conclude that sickle-cell hemoglobin exhibits
A) altered primary structure.
B) altered secondary structure.
C) altered tertiary structure.
D) altered quaternary structure.
E) altered primary structure and altered quaternary structure; the secondary and tertiary structures may or may not be altered.
Cervical cancer (a) Top view of the uterus showing the presence of a tumor in the wall of the cervix
Some of the many small molecules found in cells
Normal right tympanic membrane
Electrophoresis gel in a densitometer. SPE densitometry showing a normal pattern.
A thick filament of myosin II molecules
The traditional human karyotypes derived from a normal female and a normal male