Patients with sickle cell disease suffer from vaso-occlusive crises because:
a. The altered hemoglobin facilitates the formation of bar-shaped hemoglobin crystals that occlude blood vessels.
b. The altered hemoglobin impairs the hemoglobin's ability to effectively transport oxygen that causes vaso-occlusion.
c. The altered hemoglobin facilitates tactoid crystal formation that alters the shape of the red blood cell, resulting in impeded blood flow in vessels.
d. The altered hemoglobin interferes with globin chain assembly, which impedes blood flow in the vessels.
Question 2
Hemoglobin C disease has altered solubility properties similar to hemoglobin S disease. What accounts for this altered solubility?
a. Heme iron is in the ferric form rather than ferrous form.
b. The hemoglobin remains in the tense structure.
c. A nonpolar amino acid is substituted for a polar amino acid.
d. A polar amino acid is substituted near the pocket where heme binds.
Response of a yeast cell to glucose
Photograph of the flea that transmits Yersinia pestis to cause bubonic plague, called the oriental r
sperm cell
Mechanism of penicillin: (a) Bacterial cell wall strengthened by peptide cross-links. (b) Penicillin ...
IgM only, then IgD and IgM on the surface of a B cell.
Structure of a typical cell membrane