Chapter 28: Structure and Function of the Hematologic System

Question 1

What is the most abundant class of plasma protein?

a. Globulin
c. Clotting factors
b. Albumin
d. Complement proteins

Answer 1

ANS: B
Albumin (approximately 60% of total plasma protein at a concentration of about 4 g/dl) is
the most abundant plasma protein.
PTS: 1 REF: Page 946

Question 2

What is the effect of low plasma albumin?
a. Clotting factors decrease, thus increasing the chance of prolonged bleeding.
b. Fewer immunoglobulins are synthesized, thus impairing the immune function.
c. Less iron is stored, thus increasing the incidence of iron deficiency anemia.
d. Osmotic pressure decreases, thus water moves from the capillaries to the
interstitium.

Answer 2

ANS: D
In the case of decreased production (e.g., cirrhosis, other diffuse liver diseases, protein
malnutrition) or excessive loss of albumin (e.g., certain kidney diseases, extensive burns),
the reduced oncotic pressure leads to excessive movement of fluid and solutes into the
tissues and decreased blood volume. The other options are not accurate descriptions of the
effect of low plasma albumin.
PTS: 1 REF: Page 946

Question 3

What is the life span of an erythrocyte (in days)?

a. 20 to 30
c. 100 to 120
b. 60 to 90
d. 200 to 240

Answer 3

ANS: C
Because it cannot undergo mitotic division, the erythrocyte has a limited life span of
approximately 120 days.
PTS: 1 REF: Pages 947-948

Question 4

Which statement concerning erythrocytes is true?

a. Erythrocytes contain a nucleus, mitochondria, and ribosomes.
b. Erythrocytes synthesize proteins.
c. Erythrocytes have the ability to change shape to squeeze through microcirculation.
d. Erythrocyte colony-stimulating factor (E-CSF) stimulates erythrocytes.

Answer 4

ANS: C
Reversible deformity enables the erythrocyte to assume a more compact torpedo-like
shape, squeeze through the microcirculation, and return to normal. The other options are
not accurate statements about erythrocytes.

Question 5

Granulocytes that contain granules of vasoactive amines, such as histamine, are called:

a. Neutrophils
c. Monocytes
b. Eosinophils
d. Basophils

Answer 5

ANS: D
Basophils contain cytoplasmic granules that hold an abundant mixture of biochemical
mediators, including histamine, chemotactic factors, proteolytic enzymes, and an
anticoagulant (heparin) (see Figure 27-3, C). This is not an accurate description of any of
the other options.
PTS: 1 REF: Page 949

Question 6

Which of the following are formed elements of the blood that are not cells but are
disk-shaped cytoplasmic fragments essential for blood clotting?
a. Monocytes
c. Macrophages
b. Platelets
d. Erythrocytes

Answer 6

ANS: B
Platelets (thrombocytes) are not true cells but are disk-shaped cytoplasmic fragments that
are essential for blood coagulation and control of bleeding. This description is not accurate
for any of the other options.
PTS: 1 REF: Pages 950-951

Question 7

Blood cells that differentiate into macrophages are known as:

a. Monocytes
c. Eosinophils
b. Neutrophils
d. Basophils

Answer 7

ANS: A
Only monocytes migrate into a variety of tissues and fully mature into tissue
macrophages and myeloid dendritic cells (see Table 27-3).
PTS: 1 REF: Page 950

Question 8

Without prior exposure to an antigen, which cells are able to destroy some types of tumor
cells and some virus-infected cells?
a. Lymphocytes 
c. Megakaryocytes
b. Plasma cells 
d. Natural killer (NK) cells

Answer 8

ANS: D
NK cells, which resemble large granular lymphocytes, kill some types of tumor cells (in
vitro) and some virus-infected cells without being induced by previous exposure to these
antigens. This capability is not true of the other options.
PTS: 1 REF: Page 950

Question 9

What is the life span of platelets (in days)?

a. 10
c. 90
b. 30
d. 120

Answer 9

ANS: A
A platelet circulates for approximately 10 days and ages. Macrophages of the mononuclear
phagocyte system, mostly in the spleen, remove platelets.
PTS: 1 REF: Page 951

Question 10

Fetal hematopoiesis occurs in which structure?

a. Gut
c. Bone marrow
b. Spleen
d. Thymus

Answer 10

ANS: B
The spleen is the largest of the secondary lymphoid organs and the site of fetal
hematopoiesis.
PTS: 1 REF: Page 951

Question 11

What is the consequence of a splenectomy?

a. The level of iron in circulation increases.
b. Antibody production increases to improve immune function.
c. The number of defective cells in circulation increases.
d. The number of clotting factors increases.

Answer 11

ANS: C
Splenic absence from any cause (e.g., atrophy, traumatic injury, removal because of
disease) has several secondary effects on the body, among them an increase in
morphologically defective blood cells in the circulation, confirming the spleen’s role in
removing old or damaged cells. This description of the consequence of a splenectomy is
not accurate for the other options.
PTS: 1 REF: Pages 951-952

Question 12

During an infection, why do lymph nodes enlarge and become tender?

a. B lymphocytes proliferate.
b. The nodes are inflamed.
c. The nodes fill with purulent exudate.
d. The nodes are not properly functioning.

Answer 12

ANS: A
The B lymphocyte proliferation in response to significant antigen (e.g., during infection)
may result in lymph node enlargement and tenderness (reactive lymph node). This
description is not accurate for the other options.
PTS: 1 REF: Page 954

Question 13

Which blood cells are the chief phagocytes involved in the early inflammation process?

a. Neutrophils
c. Eosinophils
b. Monocytes
d. Erythrocytes

Answer 13

ANS: A
Neutrophils are the chief phagocytes of early inflammation.
PTS: 1 REF: Page 949

Question 14

Which blood cells are biconcave in shape and have the capacity to be reversibly
deformed?
a. Neutrophils 
c. Eosinophils
b. Monocytes 
d. Erythrocytes

Answer 14

ANS: D
The erythrocyte’s size and shape are ideally suited to its function as a gas carrier. A red
blood cell (RBC) is a small disk with two unique properties: (1) a biconcave shape and (2)
the capacity to be reversibly deformed. These are characteristics not observed in any of the
other options.
PTS: 1 REF: Page 948

Question 15

Which hemoglobin is made from oxidized ferric iron (Fe3+) and lacks the ability to bind
oxygen?
a. Deoxyhemoglobin 
c. Methemoglobin
b. Oxyhemoglobin 
d. Glycosylated hemoglobin

Answer 15

ANS: C
Without reactivation by methemoglobin reductase, the Fe3+-containing hemoglobin
(methemoglobin) cannot bind oxygen. This capability is not true of the other types of
hemoglobin mentioned.
PTS: 1 REF: Page 961

Question 16

The absence of parietal cells would prevent the absorption of an essential nutrient
necessary to prevent which type of anemia?
a. Iron deficiency
c. Folic acid deficiency anemia
b. Pernicious anemia
d. Aplastic anemia

Answer 16

ANS: B
Dietary vitamin B12 is a large molecule that requires a protein secreted by parietal cells
into the stomach (intrinsic factor [IF]) to transport across the ileum. Defects in IF
production lead to decreased B12 absorption and pernicious anemia. The other options are
not the result of this process.
PTS: 1 REF: Page 962

Question 17

Which nutrients are necessary for the synthesis of DNA and the maturation of
erythrocytes?
a. Protein and niacin 
c. Cobalamin (vitamin B12) and folate
b. Iron and vitamin B6 (pyridoxine) 
d. Pantothenic acid and vitamin C

Answer 17

ANS: C
Cobalamin and folate are necessary for the synthesis of DNA and for the maturation of
erythrocytes. The remaining options are not necessary for these processes to occur.
PTS: 1 REF: Page 962 | Table 27-6

Question 18

Which nutrients are necessary for hemoglobin synthesis?

a. Protein and niacin
c. Cobalamin (vitamin B12) and folate
b. Iron and vitamin B6 (pyridoxine)
d. Pantothenic acid and vitamin C

Answer 18

ANS: B
Iron and B6 (pyridoxine) are necessary for hemoglobin synthesis (see Table 27-6). The
remaining options are not necessary for hemoglobin synthesis.
PTS: 1 REF: Page 962 | Table 27-6

Question 19

Recycling of iron from erythrocytes is made possible by which of the following?

a. Transferrin
c. Apoferritin
b. Hemosiderin
d. Erythropoietin

Answer 19

ANS: A
Transferrin is recycled (transferrin cycle) in the following manner: (1) the transferrin-iron
complex binds to a transferring receptor on the erythroblast’s plasma membrane; (2) the
complex moves into the cell by receptor-mediated endocytosis; (3) iron is released
(dissociated) from transferrin; and (4) the dissociated transferrin is returned to the
bloodstream for reuse. The other options do not present an accurate description of the
recycling of erythrocytic iron.
PTS: 1 REF: Pages 963-964

Question 20

By which structure are mature erythrocytes removed from the bloodstream?

a. Liver
c. Thymus
b. Lymph nodes
d. Spleen

Answer 20

ANS: D
After approximately 100 to 120 days in the circulation, old erythrocytes are removed by
tissue macrophages, primarily in the spleen.
PTS: 1 REF: Page 962

Question 21

Which substance is used to correct the chronic anemia associated with chronic renal
failure?
a. Iron 
c. Cobalamin (vitamin B12)
b. Erythropoietin 
d. Folate

Answer 21

ANS: B
One of the most significant advances in the study of hematopoietic growth factors has
been the development of erythropoietin for individuals with chronic renal failure. The
other options are not associated with the treatment of chronic anemia.
PTS: 1 REF: Pages 960-961

Question 22

What is the role of thromboxane A (TXA2) in the secretion stage of hemostasis?

a. Stimulates the synthesis of serotonin.
b. Promotes vasodilation.
c. Stimulates platelet aggregation.
d. Promotes formation of cyclooxygenase.

Answer 22

ANS: C
Platelet aggregation is primarily stimulated by TXA2 and adenosine diphosphate (ADP),
which induce functional fibrinogen receptors on the platelet. Th

Question 23

Which of the following is the role of nitric oxide (NO) in hemostasis?
a. Stimulates the release of fibrinogen to maintain the platelet plug.
b. Stimulates the release of clotting factors V and VII.
c. Causes vasoconstriction and stimulates platelet aggregation.
d. Controls platelet activation through cyclic adenosine monophosphate
(cAMP)–mediated signaling.

Answer 23

ANS: D
Endothelial cell NO synthase produces NO, which controls platelet activation through
cAMP-mediated signaling. The other options do not present an accurate description of the
role of NO in hemostasis.
PTS: 1 REF: Page 966 | Figure 27-18

Question 24

The drug heparin acts in hemostasis by which processes?

a. Inhibiting thrombin and antithrombin III (AT-III)
b. Preventing the conversion of prothrombin to thrombin
c. Shortening the fibrin strands to retract the blood clot
d. Degrading the fibrin within blood clots

Answer 24

ANS: A
Clinically administered heparin or heparin sulfate (on the surface of endothelial cells)
binds to AT-III and induces a conformational change that greatly enhances its activity.
Under normal conditions, the presence of endothelial cell heparin sulfate and available
AT-III in the circulation cooperate to protect the vessels from the effects of spontaneously
activated thrombin. The other options do not accurately describe the role heparin plays in
hemostasis.
PTS: 1 REF: Page 970

Question 25

What is plasmin’s role in the clotting process?

a. Stimulates platelet aggregation.
b. Inhibits platelet adhesion and aggregation.
c. Prevents the conversion of prothrombin to degrade the fibrin within blood clots.
d. Degrades the fibrin within blood clots.

Answer 25

ANS: D
Plasmin (also called fibrinase or fibrinolysin) is a serine protease that degrades fibrin
polymers in clots. It is not capable of the functions described in the remaining options.
PTS: 1 REF: Pages 971-972

Question 26

What does polycythemia at birth indicate?

a. Hypoxia in utero
c. Congenitally absent spleen
b. Dysfunctional bone marrow
d. Dehydration in utero

Answer 26

ANS: A
The hypoxic intrauterine environment stimulates erythropoietin production in the fetus and
accelerates fetal erythropoiesis, producing polycythemia (excessive proliferation of
erythrocyte precursors) of the newborn. The other options are not related to polycythemia.
PTS: 1 REF: Page 975

Question 27

Where are Kupffer cells located?

a. Kidneys
c. Pancreas
b. Liver
d. Spleen

Answer 27

ANS: B
The liver macrophages are the only location for Kupffer cells.
PTS: 1 REF: Page 950 | Page 962 | Table 27-3

Question 28

Where are Langerhans cells found?

a. Skin
c. Kidney
b. Intestinal lining
d. Thyroid

Answer 28

ANS: A
Of the available options, only the skin is the location for Langerhans cells.
PTS: 1 REF: Page 950 | Table 27-3

Question 29

What is the role of collagen in the clotting process?

a. Initiates the clotting cascade.
c. Stimulates fibrin.
b. Activates platelets.
d. Deactivates fibrinogen

Answer 29

ANS: B
In the clotting process, collagen provides a particularly strong stimulus to activate
platelets. Collagen does not bring about any of the other options.
PTS: 1 REF: Page 969

Question 30

Which form of iron (Fe) can be used in the formation of normal hemoglobin?

a. Fe+
c. Fe3+
b. Fe2+
d. Fe4+

Answer 30

ANS: B
It is crucial that the iron be correctly charged; only reduced ferrous iron (Fe2+) can bind
oxygen in the lungs and release it in the tissues.
PTS: 1 REF: Page 961

Question 31

Where are alveolar macrophages found?

a. Skin
c. Gastrointestinal tract
b. Breasts
d. Lungs

Answer 31

ANS: D
The lung is the only location for alveolar macrophages.
PTS: 1 REF: Page 950 | Table 27-3

Question 32

What changes to the hematologic system is related to age?

a. Platelet adhesiveness decreases.
b. Lymphocyte function decreases.
c. Cellular immunity increases.
d. Erythrocyte reproduction accelerates.

Answer 32

ANS: B
Blood composition changes little with age. A delay in erythrocyte replenishment may
occur after bleeding, presumably because of iron deficiency. Lymphocyte function appears
to decrease with age. Particularly affected is a decrease in cellular immunity. Platelet
adhesiveness probably increases with age.
PTS: 1 REF: Page 975

Question 33

What is the function of erythrocytes?

a. Tissue oxygenation
c. Infection control
b. Hemostasis
d. Allergy response

Answer 33

ANS: A
Erythrocytes are solely responsible for tissue oxygenation.
PTS: 1 REF: Pages 947-948

Question 34

Which characteristics allow erythrocytes to function as gas carriers? (Select all that apply.)

a. Permanent shape
b. Compactness
c. Reversible deformability
d. Presence of hyperactive mitochondria
e. Biconcavity

Answer 34

ANS: C, E
A red blood cell (RBC) is a small disk with two unique properties: (1) a biconcave shape
and (2) the capacity to be reversibly deformed. The other options are not relevant to the
function of gas transport.
PTS: 1 REF: Page 948

Question 35

Which statements about plasma proteins are correct? (Select all that apply.)

a. Provide clotting factors.
b. Transport triglycerides.
c. Synthesize complement proteins.
d. Create hydrostatic pressure.
e. Transport cholesterol.

Answer 35

ANS: A, B, C, E
Plasma proteins do not create hydrostatic pressure. The other options are all accurate
statements regarding plasma proteins.
PTS: 1 REF: Pages 945-947

Question 36

What are the primary anticoagulant mechanisms? (Select all that apply.)

a. Antithrombin III
b. Tissue factor pathway inhibitor
c. Hematopoiesis
d. Protein C
e. Phagocytosis

Answer 36

ANS: A, B, D
The major regulatory factors that control hemostasis reside where the greatest probability
of clotting would occur—on the endothelial cell surface. The primary anticoagulant
mechanisms include thrombin inhibitors (e.g., antithrombin III), tissue factor inhibitors
(e.g., tissue factor pathway inhibitor), and mechanisms for degrading activated clotting
factors (e.g., protein C). Hematopoiesis and phagocytosis are processes that are not related
to anticoagulation.
PTS: 1 REF: Page 970

Question 37

Which statements are true regarding the role of the endothelium in clot formation? (Select
all that apply.)
a. The surface of the endothelium produces plasma protease inhibitors.
b. Plasma protease inhibitors assist in preventing clot formation.
c. Thrombomodulin is a protein that is converted on the surface of endothelial cells.
d. Protein A binds to thrombomodulin.
e. Activated protein C enhances the adhesion ability of neutrophils

Answer 37

ANS: A, B, C
The surface of the endothelium produces plasma protease inhibitors to resist clot
formation. Thrombomodulin is a membrane thrombin-binding protein matter and is
converted to activated protein C (see Figure 27-18) on the surface of endothelial cells.
Protein C in the circulation binds to thrombomodulin. Activated protein C inhibits the
adhesion of neutrophils to the endothelium.
PTS: 1 REF: Pages 970-971

Question 38

Which statements characterize albumin? (Select all that apply.)

a. Retains sodium to maintain water balance.
b. Provides colloid osmotic pressure.
c. Is synthesized in the liver.
d. Is a carrier for drugs that have low water solubility.
e. Is a small molecule

Answer 38

ANS: B, C, D
Albumin is a plasma protein produced by the liver. It serves as a carrier molecule for the
normal components of blood, as well as for drugs that have low solubility in water (e.g.,
free fatty acids, lipid-soluble hormones, thyroid hormones, bile salts). Albumin molecules
are large and do not diffuse freely through the vascular endothelium, thus they maintain
the critical colloidal osmotic pressure (or oncotic pressure) that regulates the passage of
water and solutes into the surrounding tissues (see Chapters 1 and 3).
PTS: 1 REF: Page 946

Question 39

Match the descriptions with the corresponding terms.
\_\_\_\_\_\_ A. Clotting
\_\_\_\_\_\_ B. Red blood cell development
\_\_\_\_\_\_ C. Red blood cell destruction
\_\_\_\_\_\_ D. Platelet formation
\_\_\_\_\_\_ E. Blood cell production

39. Endomitosis
40. Hemostasis
41. Hematopoiesis
42. Erythropoiesis
43. Phagocytosis

Answer 39

39. ANS: D PTS: 1 REF: Page 965
    MSC: During thrombopoiesis, the megakaryocyte progenitor is programmed to undergo an
    endomitotic cell cycle called endomitosis, during which DNA replication of platelets occurs.
40. ANS: A PTS: 1 REF: Page 965
    MSC: Hemostasis is defined as arrest of bleeding.
41. ANS: E PTS: 1 REF: Page 954
    MSC: Blood cell production (hematopoiesis) is ongoing, occurring in the liver and spleen of the
    fetus and only in bone marrow (medullary hematopoiesis) after birth.
42. ANS: B PTS: 1 REF: Page 959
    MSC: It was not until the 1850s that the bone marrow was identified as the site of erythropoiesis,
    or the development of red blood cells.
43. ANS: C PTS: 1 REF: Page 950
    MSC: Monocytes and macrophages are active phagocytes that participate in the immune and
    inflammatory responses. They also ingest dead or defective host cells, particularly blood cells.