Q: A laboratory technician is asked to calculate the mean corpuscular hemoglobin (MCH) for a patient with the following values: hemoglobin (Hb) = 15.0 g/dL, RBC count = $$5.0 x 10^6$$/μL. Which formula should be used, and what is the correct answer?

Use $$\text{MCH} = \frac{\text{Hb} \times 10}{\text{RBC}}$$; MCH = 30 pg

Question 1

Which of the following best describes the primary function of erythrocytes (RBCs) in the circulatory system?

Accepted Answer

To transport oxygen to tissues and remove carbon dioxide from tissues

Question 2

A patient presents with fatigue and pallor. Laboratory results show a low hemoglobin concentration and a low mean corpuscular volume (MCV). Which of the following is the most likely explanation for these findings?

Accepted Answer

The patient has iron deficiency anemia, resulting in microcytic, hypochromic RBCs

Question 3

Which vessel type is primarily responsible for the exchange of oxygen and carbon dioxide between blood and tissues?

Accepted Answer

Capillaries

Question 4

A laboratory technician is asked to calculate the mean corpuscular hemoglobin (MCH) for a patient with the following values: hemoglobin (Hb) = 15.0 g/dL, RBC count = $$5.0 x 10^6$$/μL. Which formula should be used, and what is the correct answer?

Accepted Answer

Use $$	ext{MCH} = \frac{	ext{Hb} 	imes 10}{	ext{RBC}}$$; MCH = 30 pg

Question 5

Which of the following statements about veins is correct?

Accepted Answer

Veins contain valves to ensure one-way blood flow toward the heart

Question 6

A blood sample is centrifuged in a microhematocrit tube. Which layer contains the majority of white blood cells and platelets?

Accepted Answer

The buffy coat between the plasma and RBC layers

Question 7

Which of the following best explains why EDTA is used as an anticoagulant in hematology testing?

Accepted Answer

EDTA chelates calcium ions, preventing blood clotting

Question 8

A patient’s hematocrit (Hct) is 42% and their RBC count is $$4.2 x 10^6$$/μL. What is the mean corpuscular volume (MCV) of this patient’s RBCs? Use the formula $$	ext{MCV} = \frac{	ext{Hct} 	imes 10}{	ext{RBC}}.$$

Accepted Answer

MCV = 100 fL

Question 9

Which of the following is a correct reference range for hemoglobin in adult females?

Accepted Answer

12.3–15.3 g/dL

Question 10

During erythropoiesis, which of the following changes occurs as a red blood cell matures?

Accepted Answer

The cell decreases in size and loses its nucleus

Question 11

A patient’s blood sample is analyzed and found to have a mean corpuscular hemoglobin concentration (MCHC) of 28 g/dL. What does this value suggest?

Accepted Answer

The patient’s RBCs are hypochromic, possibly indicating anemia

Question 12

Which of the following best describes the role of hemoglobin in red blood cells?

Accepted Answer

Hemoglobin binds oxygen in the lungs and releases it in the tissues

Question 13

A laboratory test result shows a hematocrit of 36% in a female patient. Which of the following best describes this result?

Accepted Answer

It is at the lower end of the normal reference range for females

Question 14

Which of the following is a correct sequence for the sites of hematopoiesis during human development?

Accepted Answer

Yolk sac → fetal liver → bone marrow

Question 15

A patient’s hemoglobin is measured using the cyanmethemoglobin method. What is the principle behind this method?

Accepted Answer

Hemoglobin is converted to a stable colored compound measured photometrically

Question 16

Which of the following best explains why iron is essential for erythropoiesis?

Accepted Answer

Iron is a component of the heme group in hemoglobin, necessary for oxygen binding

Question 17

A patient’s blood sample has a hemoglobin of 12 g/dL and a hematocrit of 36%. Using the relationship $$	ext{Hct} = 	ext{Hb} 	imes 3$$, is this result consistent with the expected ratio?

Accepted Answer

Yes, because $$12 	imes 3 = 36$$

Question 18

Which of the following is a function of thrombocytes (platelets)?

Accepted Answer

Forming a plug to stop bleeding in injured vessels

Question 19

A patient with a genetic mutation in the beta-globin chain of hemoglobin is most likely to have which of the following conditions?

Accepted Answer

Sickle cell anemia

Question 20

Which of the following laboratory tests is NOT typically included in a complete blood count (CBC)?

Accepted Answer

Blood glucose level

Principles and Practice of Clinical Hematology: Study Notes

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Study Guide - Flashcards