Blood and Lymphatic System Practice Quiz (33 questions)

1. A person's blood helps maintain a stable internal environment; which set of functions best describes how it does so?

A. It produces digestive enzymes, stores oxygen, regulates blood-cell production, and maintains fluid in the lungs.

B. It transports nutrients and hormones, produces antibodies, controls bone growth, and keeps blood pH fixed at 7.0.

C. It transports gases, nutrients, and wastes, supports defense and coagulation, regulates temperature, and buffers pH.

D. It supports clotting and defense, removes carbon dioxide, stores metabolic wastes, and regulates temperature through the kidneys.

Answer: (C)

Explanation

Blood transports oxygen, nutrients, carbon dioxide, and wastes, while also supporting immune defense and coagulation, regulating temperature around 37°C, and buffering pH. The kidney-centered alternative confuses blood's temperature and pH-regulating roles with functions assigned to other organs.

2. A laboratory measures the volume fraction of blood cells in a blood sample; what is this measurement called?

A. The hematocrit, which represents the blood-cell fraction of total blood volume.

B. The hemoglobin concentration, which represents the percentage of cells in total blood volume.

C. The buffy-coat fraction, which represents the volume of all blood cells in total blood volume.

D. The plasma fraction, which represents the liquid component of total blood volume.

Answer: (A)

Explanation

Hematocrit is the volume fraction of blood cells in total blood volume; it averages about 46% in men and 42% in women. Plasma is the liquid fraction, so calling the cell fraction the plasma fraction reverses the distinction.

3. Which description most accurately represents the approximate composition of blood plasma?

A. About 55% water, 40% proteins, and 5% other substances such as ions and nutrients.

B. About 90% proteins, 8% water, and 2% other substances such as ions and nutrients.

C. About 90% water, 8% proteins, and 2% other substances such as ions and nutrients.

D. About 80% water, 18% blood cells, and 2% proteins and other substances.

Answer: (C)

Explanation

Plasma is approximately 90% water, 8% proteins, and 2% other substances, including ions, glucose, vitamins, hormones, and waste products. The alternative with 90% proteins substantially overstates their share and understates water.

4. A reduction in plasma albumin would most directly threaten which function of plasma proteins?

A. Regulating temperature by absorbing heat within the bone marrow.

B. Destroying pathogens by converting plasma into mobile phagocytic cells.

C. Producing red blood cells by supplying their nuclei and cellular membranes.

D. Maintaining colloid osmotic pressure that helps retain fluid within the bloodstream.

Answer: (D)

Explanation

Albumin and other plasma proteins help maintain colloid osmotic pressure, as well as transport substances, buffer pH, and support coagulation and defense. Producing red blood cells is not a plasma-protein function; erythrocytes develop from precursor cells in bone marrow.

5. Where does hematopoiesis occur in a healthy person, and what initiates blood-cell precursor production there?

A. In the liver, where lymphocytes directly transform into all blood-cell types without growth factors.

B. In the spleen, where mature blood cells divide in response to circulating antibodies.

C. In bone marrow, where multipotent stem cells generate precursors under the influence of growth factors.

D. In the thymus, where differentiated erythrocytes generate precursors in response to oxygen.

Answer: (C)

Explanation

Healthy hematopoiesis occurs in bone marrow, particularly in short and flat bones and the epiphyses, where multipotent stem cells produce precursors under growth-factor influence. The spleen can break down erythrocytes, but it is not the usual site of blood-cell production in healthy people.

6. A stem cell is identified as myeloid; which group of cells can it produce?

A. Granulocytes, monocytes, erythrocytes, and platelets.

B. B cells, monocytes, natural killer cells, and platelets.

C. T cells, B cells, natural killer cells, and platelets.

D. T cells, granulocytes, natural killer cells, and erythrocytes.

Answer: (A)

Explanation

Myeloid stem cells produce granulocytes, monocytes, erythrocytes, and platelets. T cells, B cells, and natural killer cells belong to the lymphoid lineage, which makes the lymphocyte-heavy alternative a plausible but incorrect match.

7. Which combination of characteristics describes a typical erythrocyte?

A. An anucleate, biconcave cell about 7.5 μm across, numbering roughly 5 million per μl.

B. A nucleated, spherical cell about 12 μm across, numbering roughly 5,000 per μl.

C. An anucleate, biconcave cell about 20 μm across, numbering roughly 50,000 per μl.

D. A nucleated, biconcave cell about 7.5 μm across, numbering roughly 5 million per μl.

Answer: (A)

Explanation

Erythrocytes are anucleate, biconcave cells approximately 7.5 μm in diameter, with a count of about 5 million per μl. A nucleated cell of that same approximate size is not consistent with the stated erythrocyte characteristics.

8. After oxygen deficiency stimulates erythropoietin release from the kidney, what is the typical lifespan and main breakdown site of erythrocytes?

A. About 10 hours, with breakdown mainly in the lungs and also in the kidney and thymus.

B. About one year, with breakdown mainly in the bone marrow and also in the lungs and skin.

C. About three days, with breakdown mainly in the liver and also in the spleen and lymph nodes.

D. About 120 days, with breakdown mainly in the spleen and also in the liver and bone marrow.

Answer: (D)

Explanation

Erythrocytes live for about 120 days and are broken down mainly in the spleen, as well as in the liver and bone marrow. The three-day lifespan is associated with circulating monocytes, not erythrocytes.

9. A blood-cell count shows approximately 5,000 cells per μl that have nuclei and can move through tissues; which cells are being counted?

A. Erythrocytes involved in oxygen transport and present at about 5 million per μl.

B. Platelets involved in coagulation and present at about 5,000 per μl.

C. Plasma proteins involved in transport and defense and present as mobile cells.

D. Leukocytes involved in defense against pathogens and in inflammatory processes.

Answer: (D)

Explanation

Leukocytes are nucleated, mobile cells that participate in defense against foreign substances and pathogens and in inflammatory processes; their total count is about 5,000 per μl. Erythrocytes also circulate in blood, but they are anucleate and occur at a much higher count.

10. A rapid response to bacteria and dead-cell debris at a mucosal site is needed; which leukocyte is especially suited to this early defense?

A. Monocytes, which remain in circulation for weeks and make up about 50–70% of leukocytes.

B. Basophils, which engulf bacteria and debris and make up about 50–70% of leukocytes.

C. Eosinophils, which chiefly target bacteria and debris and make up about 50–70% of leukocytes.

D. Neutrophils, which phagocytose bacteria and debris and make up about 50–70% of leukocytes.

Answer: (D)

Explanation

Neutrophils are an early bacterial defense: they migrate especially to mucous membranes and phagocytose bacteria and dead-cell debris. Eosinophils are more closely associated with defense against parasites, especially worms, rather than this early bacterial response.

11. What typically happens after a circulating monocyte enters tissue?

A. It differentiates into a B lymphocyte that makes antibodies and circulates for several hours.

B. It differentiates into a macrophage that can phagocytose microorganisms and present antigens.

C. It differentiates into an erythrocyte that transports oxygen and presents antigens.

D. It differentiates into a neutrophil that releases granules against parasites and allergies.

Answer: (B)

Explanation

Monocytes enter tissues and differentiate into macrophages, which phagocytose microorganisms and present antigens. B lymphocytes form specific antibodies and present antigens, but they are not the tissue-differentiated form of circulating monocytes.

12. Which pairing correctly matches lymphocyte types with their roles in immune defense?

A. T cells defend against viruses, B cells mediate specific defense without antibodies, and natural killer cells present antigens.

B. T cells mediate specific defense, B cells form specific antibodies and present antigens, and natural killer cells defend against viruses.

C. T cells form specific antibodies, B cells defend against viruses, and natural killer cells present antigens in specific defense.

D. T cells phagocytose bacteria, B cells defend against parasites, and natural killer cells form specific antibodies.

Answer: (B)

Explanation

T lymphocytes mediate specific defense, B lymphocytes form specific antibodies and present antigens, and natural killer cells defend against viruses. The alternative assigning antibody formation to T cells and viral defense to B cells swaps the roles of the lymphocyte types.

13. Which sequence describes primary hemostasis after a blood vessel is injured?

A. Platelets adhere to intact vessel walls, coagulation factors are activated, and a red thrombus forms.

B. Fibrinogen is cleaved first, platelets disperse, and a white thrombus forms.

C. The vessel constricts, platelets adhere to the wound, and platelet aggregation forms a white thrombus.

D. The vessel constricts, fibrin forms a mesh, and erythrocytes produce a red thrombus.

Answer: (C)

Explanation

Primary hemostasis involves vessel constriction followed by platelet adhesion and aggregation into a white thrombus. A fibrin mesh containing erythrocytes characterizes secondary hemostasis and produces a red thrombus.

14. What occurs during secondary hemostasis to create a firm red thrombus?

A. Platelets shed cytoplasm into the circulation, where the fragments clump into a red mass.

B. Activated coagulation factors cleave fibrinogen into fibrin, which forms a mesh containing platelets and erythrocytes.

C. Smooth muscle constricts the vessel while von Willebrand factor attaches platelets to its wall.

D. Platelets adhere to the wound and aggregate into a white plug without a fibrin mesh.

Answer: (B)

Explanation

In secondary hemostasis, coagulation factors activate one another and convert fibrinogen to fibrin, whose mesh traps platelets and erythrocytes. Platelet adhesion and aggregation into a white thrombus describe primary hemostasis.

15. How are platelets formed and where are they broken down?

A. They form by division of mature erythrocytes in the spleen and are broken down in bone marrow.

B. They form by fragmentation of endothelial cells in blood vessels and are broken down in the heart.

C. They form from plasma proteins in the liver and are broken down in the kidneys and lungs.

D. They form from cytoplasm shed by bone-marrow megakaryocytes and are broken down in the spleen and liver.

Answer: (D)

Explanation

Platelets are small discs produced when megakaryocytes in bone marrow shed cytoplasm; their breakdown occurs in the spleen and liver. Mature erythrocytes do not divide to produce platelets.

16. Which storage and clinical-use profile matches erythrocyte concentrates?

A. Stored at 20–24°C for five days and used to treat bleeding caused by thrombocytopenia.

B. Stored at −30 to −40°C for two years and used to replace plasma proteins and coagulation factors.

C. Stored at 4°C for five days and used primarily to replace coagulation factors.

D. Stored at 4°C for 42 days and used to treat anemia, including after major blood loss.

Answer: (D)

Explanation

Erythrocyte concentrates are stored at 4°C for 42 days and are used for anemia, including anemia following major blood loss. The 20–24°C, five-day profile applies to platelet concentrates, which address thrombocytopenia-related bleeding.

17. A patient with thrombocytopenia has a bleeding tendency. Which blood product and storage conditions best match this need?

A. Platelet concentrates stored at 4°C for 42 days.

B. Platelet concentrates stored at 20–24°C for five days.

C. Erythrocyte concentrates stored at 4°C for 42 days.

D. Fresh frozen plasma stored at −30 to −40°C for two years.

Answer: (B)

Explanation

Platelet concentrates are used for bleeding tendencies caused by thrombocytopenia and are stored at 20–24°C for five days. Erythrocyte concentrates replace red cells and do not address the platelet deficiency described.

18. In massive blood loss or consumptive coagulopathy, which product can replace proteins and coagulation factors?

A. Fresh frozen plasma, stored at −30 to −40°C for two years.

B. Platelet concentrates, stored at 20–24°C for five days.

C. Fresh frozen plasma, stored at 4°C for 42 days.

D. Erythrocyte concentrates, stored at 4°C for 42 days.

Answer: (A)

Explanation

Fresh frozen plasma replaces proteins and coagulation factors and may be used in massive blood loss or consumptive coagulopathy. Erythrocyte concentrates replace red cells rather than plasma proteins and coagulation factors.

19. What are ABO antigens in the context of blood groups?

A. Coagulation proteins that circulate in plasma and form fibrin during clotting.

B. Clumps of erythrocytes formed when antibodies react with cells in a blood sample.

C. Surface structure variants on erythrocytes that may be recognized as foreign in another person's blood.

D. Serum substances that bind to surface structures and defend against foreign material.

Answer: (C)

Explanation

ABO antigens are variant structures on erythrocyte surfaces that may be recognized as foreign in another person's blood. Serum substances that defend against antigens are antibodies, not antigens.

20. What does agglutination mean in an ABO blood reaction?

A. Conversion of fibrinogen into fibrin during coagulation.

B. Attachment of platelets to a damaged vessel wall during primary hemostasis.

C. Clumping of erythrocytes after their surface structures react with IgM antibodies.

D. Recognition of an erythrocyte surface structure as foreign by another person's immune system.

Answer: (C)

Explanation

In the ABO system, erythrocyte surface structures can react with IgM antibodies and cause agglutination, meaning cells clump together. An antigen is the surface structure recognized as foreign, not the clumping itself.

21. Which statement correctly distinguishes rhesus-positive from rhesus-negative erythrocytes and describes anti-D formation?

A. Rhesus-positive cells lack the D antigen, while rhesus-negative cells carry it; anti-D is present from birth in both groups.

B. Rhesus-positive cells carry the D antigen, while rhesus-negative cells lack it; a rhesus-negative person may develop anti-D after contact with D-positive blood.

C. Rhesus-positive cells carry the D antigen, while rhesus-negative cells lack it; anti-D is present from birth in rhesus-negative people.

D. Both cell types carry the D antigen, but rhesus-negative people may develop anti-D after contact with D-negative blood.

Answer: (B)

Explanation

Rhesus-positive erythrocytes have D antigen, whereas rhesus-negative erythrocytes lack it; anti-D is not present from birth and may develop after a rhesus-negative person encounters D-positive blood. The claim that anti-D is present from birth reverses this key distinction.

22. How can a rhesus-negative mother's anti-D antibodies affect a later pregnancy with a rhesus-positive child?

A. She may form IgM anti-D at the first conception, which remains outside the placenta and causes maternal erythrocyte clumping.

B. She may form IgG anti-D after delivery, which protects a later D-positive fetus by preventing erythrocyte destruction.

C. After exposure to the first child's D-positive cells, she may form IgG anti-D that crosses the placenta and destroys fetal erythrocytes in a later pregnancy.

D. Her exposure to D-positive cells causes the fetus to lose its D antigen, preventing maternal antibodies from affecting fetal cells.

Answer: (C)

Explanation

Exposure to a rhesus-positive child's erythrocytes at birth may prompt a rhesus-negative mother to form IgG anti-D; in a later pregnancy, these antibodies can cross the placenta and destroy fetal erythrocytes. The idea that maternal IgG anti-D protects the later fetus reverses its potential effect.

23. Which set of functions is performed by the lymphatic system?

A. Drainage, immune defense, and fat transport

B. Blood-cell production, gas exchange, and heat regulation

C. Nerve signaling, nutrient absorption, and blood clotting

D. Hormone secretion, waste filtration, and oxygen transport

Answer: (A)

Explanation

The lymphatic system drains tissue fluid, contributes to immune defense, and transports fats. Blood-cell production is not a substitute for this set of functions.

24. Which classification correctly distinguishes primary from secondary lymphatic organs?

A. Thymus and spleen are primary; bone marrow, lymph nodes, and MALT are secondary.

B. Spleen and lymph nodes are primary; bone marrow, thymus, and MALT are secondary.

C. Bone marrow and thymus are primary; spleen, lymph nodes, and MALT are secondary.

D. Bone marrow and lymph nodes are primary; thymus, spleen, and MALT are secondary.

Answer: (C)

Explanation

Bone marrow and thymus are primary lymphatic organs, while the spleen, lymph nodes, and MALT are secondary organs. The spleen is a secondary organ, not a primary one.

25. Which sequence best describes lymph flow toward the thoracic duct?

A. Lymph vessels → lymph capillaries → large lymphatic vessels → lymph nodes → thoracic duct → cisterna chyli

B. Lymph capillaries → lymph nodes → lymph vessels → cisterna chyli → large lymphatic vessels → thoracic duct

C. Lymph capillaries → lymph vessels → lymph nodes → large lymphatic vessels → cisterna chyli → thoracic duct

D. Lymph capillaries → lymph vessels → cisterna chyli → lymph nodes → large lymphatic vessels → thoracic duct

Answer: (C)

Explanation

Lymph passes from capillaries into lymph vessels and nodes, then into large lymphatic vessels, the cisterna chyli, and the thoracic duct. The sequence placing nodes before lymph vessels reverses the stated early flow.

26. A lymph node contains a B-cell follicle and a T-cell-rich region near the medulla; where are these regions located?

A. The B-cell follicle is in the medulla, and the T-cell-rich region lies between cortex and medulla.

B. The B-cell follicle lies between cortex and medulla, and the T-cell-rich region is in the cortex.

C. The B-cell follicle is in the cortex, and the T-cell-rich region is in the medulla.

D. The B-cell follicle is in the cortex, and the T-cell-rich region lies between cortex and medulla.

Answer: (D)

Explanation

The cortex contains mainly B-cell follicles, while the region between cortex and medulla is mainly a T-cell zone. The medulla is characterized mainly by plasma cells, not the principal T-cell zone.

27. Which description correctly matches thymic regions with their lymphocyte content and role?

A. The cortex contains T cells and precursors, while the medulla contains relatively few lymphocytes.

B. The cortex contains mature B cells, while the medulla contains T-cell precursors.

C. The cortex contains relatively few lymphocytes, while the medulla is rich in T cells and precursors.

D. The cortex is rich in plasma cells, while the medulla supports B-cell maturation.

Answer: (A)

Explanation

The thymic cortex contains T cells and their precursors, and the medulla has few lymphocytes; the thymus supports T-cell maturation and selection. A lymphocyte-rich medulla reverses the thymic pattern.

28. A developing T cell binds a self-antigen–MHC complex strongly in the thymus; what is the expected outcome?

A. It continues maturation because strong self-binding confirms useful recognition.

B. It continues development through positive selection in the cortex.

C. It undergoes apoptosis through negative selection in the medulla.

D. It undergoes clonal deletion in the bone marrow.

Answer: (C)

Explanation

Strong binding to self-antigen–MHC triggers apoptosis through negative selection in the thymic medulla. Positive selection occurs in the cortex and favors cells with low-affinity self-MHC recognition.

29. A developing B cell binds a self-antigen strongly through its receptor in bone marrow; what usually happens?

A. It undergoes apoptosis through clonal deletion.

B. It undergoes negative selection in the thymic medulla.

C. It proceeds to maturity because strong binding improves self-recognition.

D. It receives positive selection in the thymic cortex.

Answer: (A)

Explanation

Strong autoreactive B-cell receptor binding usually causes apoptosis through clonal deletion in bone marrow. Positive and negative selection in the thymus are processes associated with developing T cells.

30. What is the role of bone marrow in the development of immunocompetent cells?

A. It forms them from mature lymphocytes and matures and selects T lymphocytes.

B. It forms them from pluripotent stem cells and matures and selects T lymphocytes.

C. It forms them from thymic precursors and matures and selects both lymphocyte types.

D. It forms them from pluripotent stem cells and matures and selects B lymphocytes.

Answer: (D)

Explanation

Bone marrow forms all immunocompetent cells from a pluripotent stem cell and is the site of B-lymphocyte maturation and selection. T-cell maturation and selection are supported by the thymus.

31. Which structure is part of a bacterium's basic cellular components?

A. A membrane-bound nucleus containing bacterial chromosomes

B. A mitotic spindle that separates bacterial chromosomes

C. A nucleoid containing bacterial genetic material

D. A 80S ribosome that carries out bacterial protein synthesis

Answer: (C)

Explanation

Bacteria have a nucleoid rather than a membrane-bound nucleus, alongside components such as a cell membrane, cell wall, and 70S ribosomes. A membrane-bound nucleus is not part of the listed bacterial structure.

32. Which set consists of bacterial pathogenicity factors?

A. Cell walls, nucleoids, ribosomes, and cytosol

B. Cocci, rods, spirals, and ribosomes

C. Plasmids, flagella, cell membranes, and cytosol

D. Capsules, pili, enzymes, and toxins

Answer: (D)

Explanation

Capsules, pili, enzymes, and toxins are bacterial pathogenicity factors. Cell walls and ribosomes are structural or cellular components, not the specified set of pathogenicity factors.

33. A bacterium grows in the absence of oxygen; how is it classified by its oxygen relationship?

A. Spiral

B. Aerobic

C. Gram-positive

D. Anaerobic

Answer: (D)

Explanation

Anaerobic bacteria grow without oxygen, whereas aerobic bacteria depend on oxygen. Gram-positive describes a staining classification, not an oxygen relationship.