ASCP Hematology 2

Question 1

Sickle cell disease is caused by a substitution of which amino acid in the beta-globin chain?

Accepted Answer

Valine for glutamic acid at position 6

Answer

In sickle cell disease, valine substitutes for glutamic acid at position 6 of the beta-globin chain.

Question 2

What is the function of the reticuloendothelial system in red blood cell destruction?

Accepted Answer

Removes senescent RBCs via phagocytosis

Answer

The reticuloendothelial system (spleen, liver, bone marrow macrophages) phagocytizes and destroys aging red blood cells.

Question 3

Which finding on a CBC is most indicative of hemolytic anemia?

Accepted Answer

Increased reticulocyte count

Answer

An elevated reticulocyte count reflects increased bone marrow production in response to accelerated RBC destruction.

Question 4

Which stain is used to identify reticulocytes on a peripheral smear?

Accepted Answer

New methylene blue stain

Answer

New methylene blue is a supravital stain that precipitates residual RNA in reticulocytes, making them visible.

Question 5

A patient has an MCV of 110 fL. Which condition is most likely?

Accepted Answer

Vitamin B12 deficiency

Answer

An elevated MCV >100 fL indicates macrocytic anemia, most commonly caused by vitamin B12 or folate deficiency.

ASCP Practice Test