Question 1

What is the diameter of a macrocyte?

Accepted Answer

Macrocytes are larger than normal red blood cells with a diameter range of 9-12 µm. Option A, B, and D refer to smaller size ranges than macrocytes. Therefore, the correct answer is option C.

Question 2

Target cells may be found in which of the following conditions?

Accepted Answer

Target cells are seen in all of the conditions mentioned - thalassemia, liver disease, hemoglobin C disease, and sickle cell anemia. In target cells, the membrane is excess or too pliable, so it provides a smaller surface area for hemoglobin within the cell. The hemoglobin thus gets squeezed into smaller volumes and assumes a dense, targeted region. As a result, the cell shows up as a bull's eye.

Question 3

A microcyte is defined as having a diameter less than which value?

Accepted Answer

A microcyte is defined as having a diameter less than 7 µm.

Question 4

A patient diagnosed with anemia of chronic disorder would demonstrate:

Accepted Answer

Anemia of chronic disorder typically presents with microcytosis, where red blood cells are smaller than normal.

Question 5

Which distinctive property is characteristic of a spherocyte?

Accepted Answer

Spherocytes are abnormally round and smaller than normal erythrocytes, resulting in a decreased surface area-to-volume ratio. This abnormal shape is often seen in hemolytic anemias and can be confirmed through laboratory testing such as osmotic fragility tests. Hypochromia (A) is seen in conditions such as iron deficiency anemia where the erythrocytes have a decreased hemoglobin content. Increased surface area-to-volume ratio (B) is seen in conditions such as sickle cell anemia where the erythrocytes have an abnormal shape. Visible central pallor (D) is a normal characteristic of erythrocytes and not seen in spherocytes.

Question 6

The grading of "slight" anisocytosis and poikilocytosis would indicate what percentage of RBCs would differ from normal red cells?

Accepted Answer

Slight anisocytosis and poikilocytosis refer to the presence of a small percentage (less than 10%) of red blood cells that are abnormally shaped or sized, but the majority of the cells are still within the normal range. These terms are used to indicate mild red cell abnormalities.

Question 7

A patient diagnosed with autoimmune hemolytic anemia may have a blood smear demonstrating:

Accepted Answer

Spherocytes are commonly seen in autoimmune hemolytic anemia due to the removal of portions of the red blood cell membrane by the spleen, leading to a spherical shape.

Question 8

A 2+ grading for poikilocytosis would indicate what percentage of RBCs would differ from normal red cells?

Accepted Answer

A grading of 2+ for poikilocytosis indicates that 25-50% of red blood cells differ from normal red cells.

Question 9

A drepanocyte is another name for which red cell?

Accepted Answer

Drepanocytes are another name for sickle cells, which are red blood cells that have a crescent or sickle shape due to a genetic mutation in the beta-globin gene. This shape change can cause the cells to become stuck in blood vessels, leading to pain, organ damage, and other complications in individuals with sickle cell disease. Spherocytes are small, round red blood cells that lack a central pallor, while ovalocytes are oval-shaped red blood cells. Stomatocytes have a mouth-like appearance due to a membrane defect, and target cells have a bullseye-like appearance due to an increase in membrane surface area.

Question 10

Codocyte is another name for which type of red cell?

Accepted Answer

Codocytes are also known as target cells due to their appearance, which resembles a target or bullseye on light microscopy. This appearance is characterized by a central area of hemoglobin surrounded by a clear zone and then a peripheral ring of hemoglobin, giving the appearance of a target.

Question 11

Hypochromia is defined as any red cell having a central area of pallor of greater than which value?

Accepted Answer

Hypochromia is defined as any red cell with a central area of pallor of greater than 3 µm.

Question 12

What is the average diameter of a mature erythrocyte?

Accepted Answer

The average diameter of a mature erythrocyte (red blood cell) is typically around 7-8 µm.

Question 13

Evaluation of macrocytosis on a peripheral blood smear should include:

Accepted Answer

An evaluation of macrocytosis should include the shape of the red blood cells, as well as the presence of inclusions, and the color of the cells. Therefore, all of the choices listed - shape, presence of inclusions, and color - should be considered when evaluating macrocytosis on a peripheral blood smear.

Question 14

The mature erythrocyte, upon maturity, passes from a:

Accepted Answer

The mature erythrocyte goes from a nucleated to a non-nucleated state during its final stages of development. As it matures, the erythrocyte ejects its nucleus, resulting in a non-nucleated mature cell.

Question 15

What might cause a microcytosis?

Accepted Answer

Microcytosis refers to the presence of abnormally small red blood cells. This can be caused by a variety of factors, many of which are related to decreased hemoglobin or iron availability. Specifically, microcytosis can occur due to decreased globin synthesis or hemoglobin synthesis, ineffective iron utilization, or a deficiency of iron. Therefore, all of the choices listed can cause microcytosis.

Question 16

As cholesterol accumulates in the plasma, as in the case of patients with liver dysfunction, the cells that are observed in the blood smear are the:

Accepted Answer

Target cells are often seen in patients with liver dysfunction and cholesterol accumulation in the plasma. Spherocytes, ovalocytes, and stomatocytes are not commonly associated with this condition.

Question 17

A normal size red cell with a slit-like area of central pallor is called a:

Accepted Answer

Stomatocytes are red blood cells with a slit-like area of central pallor that resembles a mouth. They are often associated with hereditary stomatocytosis, a rare inherited disorder characterized by an increased number of stomatocytes in the blood. Drepanocytes, sickle cells, ovalocytes, and target cells all have abnormal shapes and are associated with different types of anemia.

Question 18

A 4+ grading for anisocytosis would indicate what percentage of red blood cells (RBCs) would differ from the normal red cells?

Accepted Answer

A 4+ grading for anisocytosis indicates that over 75% of the RBCs are different from the normal red cells.

Question 19

What is the primary function of hemoglobin?

Accepted Answer

The primary function of hemoglobin is to carry oxygen from the lungs to the tissues of the body. Hemoglobin is a protein found in red blood cells and is responsible for the red color of blood. It binds to oxygen molecules in the lungs and releases them in the tissues where oxygen is needed for cellular respiration.

Question 20

All of the following are proposed mechanisms of macrocytosis except:

Accepted Answer

Impaired RNA synthesis is not a proposed mechanism of macrocytosis. Macrocytosis, characterized by enlarged red blood cells, is commonly associated with mechanisms such as impaired DNA synthesis (leading to ineffective erythropoiesis and thus larger cells), accelerated erythropoiesis (which can lead to premature release of larger reticulocytes into the bloodstream), and alterations in membrane lipid composition (like increased cholesterol and lecithin, affecting the cell membrane's flexibility and size). However, impaired RNA synthesis is not directly linked to the development of macrocytosis.

Quiz 5: Evaluation of Red Blood Cell Morphology and Introduction to Platelet and White Blood Cell Morphology