Blood Physiology: Detailed Questions and Answers
1. Erythropoietin production is increased when: Living at a high altitude > 4000m for a long time.
A. True
Explanation:
* At altitudes greater than 4000m, the atmospheric pressure is lower, and the oxygen concentration in the air is also reduced. This leads to a decrease in oxygen levels in the blood.
* The body recognizes this oxygen deficiency and stimulates the production of erythropoietin (EPO) from the kidneys. EPO promotes red blood cell production in the bone marrow.
* Increased red blood cell count helps enhance oxygen transport capacity, compensating for the oxygen deficit due to the high-altitude environment.
* Therefore, living at a high altitude > 4000m for a long time will stimulate an increase in EPO production.
Note:
* It is important to distinguish between increased EPO production due to oxygen deficiency and polycythemia vera – a pathological condition that leads to excessive red blood cell production.
* Living at high altitudes > 4000m for extended periods can cause several health effects, such as: anemia, shortness of breath, fatigue, memory impairment, nausea…
2. Blood transfusion reaction will occur when: The donor’s red blood cells are destroyed.
A. True
Explanation:
* Blood transfusion reaction is an immune response that occurs when the donor’s blood is incompatible with the recipient’s blood.
* When incompatible blood is transfused, antibodies in the recipient’s plasma will recognize and attack the donor’s red blood cells, leading to agglutination (clumping) and hemolysis (red blood cell lysis).
* The destruction of the donor’s red blood cells releases hemoglobin into the blood, causing dangerous symptoms such as: fever, back pain, jaundice, kidney failure, anaphylactic shock…
Note:
* Hemolytic reaction due to incompatible blood transfusion can occur immediately or shortly after the transfusion.
* Symptoms of blood transfusion reaction are diverse and can be very serious, threatening the patient’s life.
3. The dangers of blood transfusion can be caused by the following reasons, except:
B. Transfusion of Rh+ blood to an Rh- individual for the second time.
Explanation:
- A. Transfusion of the wrong blood type belonging to the ABO blood group system: This is the most serious risk of blood transfusion reaction, potentially fatal.
- C. Transfusion of blood that does not meet quality standards: Blood that does not meet quality standards may contain bacteria, viruses, or other pathogens, posing a risk to the recipient.
- D. Transfusion of blood with a large volume and speed: Transfusing too quickly or too much blood can overload the circulation, leading to heart failure, pulmonary edema…
- E. Transfusion of Rh- blood to an Rh+ individual for the second time: This does not pose a danger because the Rh+ individual’s body does not have antibodies against Rh-.
Note:
* Transfusion of Rh+ blood to an Rh- individual for the second time can cause hemolytic disease of the newborn if the mother is pregnant for the second time.
* Choosing the correct blood type and ensuring blood quality is crucial to ensure blood transfusion safety.
4. Individuals with Rh (+) blood type are those: Having Rh factor on the red blood cell membrane.
A. True
Explanation:
* The Rh blood group system is a blood classification system based on the presence or absence of an antigen called Rh factor (Rh factor) on the surface of red blood cells.
* Individuals with Rh (+) blood type means they have the Rh factor on their red blood cell membranes.
* Individuals with Rh (-) blood type do not have the Rh factor on their red blood cell membranes.
Note:
* The Rh factor is a strong antigen that can cause serious immune reactions.
* Determining Rh blood type is essential in blood transfusions and obstetrics, especially in pregnant women.
5. Complications during Rh blood transfusion?
- In the first pregnancy, the Rh D (+) fetus develops normally if the placenta is not damaged during pregnancy.
- From the second pregnancy onwards, if the child still has Rh D (+) blood type, the mother’s body will produce antibodies (from the previous pregnancy) that cross the placenta to attack the Rh D (+) antigen on the surface of the child’s red blood cells, causing red blood cell agglutination or hemolysis.
- Consequences can cause miscarriage, stillbirth, premature birth, or intellectual disability in the child.
- Mothers carrying Rh D (-) blood type who have been pregnant with a Rh D (+) child can still experience blood transfusion complications even during the first Rh D (+) blood transfusion.
Note:
* Currently, there is a method of injecting Rhogam (an immunoglobulin antibody) to Rh (-) pregnant women to prevent the production of anti-Rh antibodies, protecting the fetus.
6. The number of white blood cells in peripheral blood: Decreases when using chloramphenicol.
A. True
Explanation:
* Chloramphenicol is an antibiotic that can inhibit protein production in the bone marrow, leading to decreased production of blood cells, including white blood cells.
* Long-term use of chloramphenicol can cause leukopenia (low white blood cell count) and increase the risk of infection.
Note:
* Chloramphenicol is an antibiotic used when other antibiotics are ineffective due to the risk of serious side effects.
* The use of chloramphenicol should be prescribed and closely monitored by a doctor.
7. When inflammation occurs:
A. Neutrophils are present within minutes.
Explanation:
* Neutrophils are the first type of white blood cells to arrive at the site of inflammation, appearing within minutes after bacterial invasion.
* Neutrophils play a crucial role in killing bacteria and other harmful agents through phagocytosis.
Note:
* Other types of white blood cells, such as macrophages and lymphocytes, also participate in the inflammatory process but appear later than neutrophils.
8. Which phenomenon in the inflammatory response occurs first when bacteria invade through the skin?
C. Phagocytosis by neutrophils and macrophages with the activation of the complement system.
Explanation:
* When bacteria invade through the skin, the complement system is activated, producing products that attract neutrophils and macrophages to the site of inflammation.
* Neutrophils and macrophages phagocytose bacteria, destroying them and releasing inflammatory mediators.
Note:
* Other phenomena such as vasodilation, increased vascular permeability, chemotaxis… also occur during the inflammatory process, but after the complement system is activated and white blood cells phagocytose bacteria.
9. In the immune response process:
A. Macrophages play a special role in initiating the immune response.
Explanation:
* Macrophages are antigen-presenting cells (APCs), they have the ability to engulf and destroy antigens, then present antigen fragments to T lymphocytes.
* The process of antigen presentation to T lymphocytes is a crucial step in generating an immune response.
Note:
* In addition to macrophages, other antigen-presenting cells such as Langerhans cells (in the skin) and dendritic cells (in lymphatic tissues) also play an essential role in the immune response.
10. Regarding the function of white blood cells: Both basophils and eosinophils increase in allergic diseases.
B. False
Explanation:
- Basophils increase in allergic diseases.
- Eosinophils increase in parasitic infections, especially helminths.
Note:
* Basophils release histamine and other inflammatory mediators that cause allergic symptoms such as itching, swelling, redness…
11. Regarding the function of white blood cells: Neutrophils and monocytes are antigen-presenting cells.
B. False
Explanation:
- Macrophages are the primary antigen-presenting cells.
- Neutrophils play a primary role in phagocytosis and killing bacteria.
- Monocytes are precursors to macrophages.
Note:
* Macrophages have the ability to engulf and destroy antigens, then present antigens to T lymphocytes, activating the immune response.
12. Regarding humoral immune response: Plasma cells produce IgG, M, A, E, D antibodies that directly kill antigens.
A. True
Explanation:
* Plasma cells are differentiated B lymphocytes, responsible for antibody production.
* Antibodies are classified into 5 main types: IgG, IgM, IgA, IgE, IgD.
* Each type of antibody has a specific function in killing antigens.
* For example, IgG is the most common type of antibody, capable of neutralizing toxins, opsonizing bacteria, activating the complement system…
Note:
* Antibodies cannot directly kill all types of antigens.
* Some antigens can persist in the body for a long time, causing chronic diseases.
13. The function of B lymphocytes:
C. Differentiate into lymphoblasts -> plasmablasts -> plasma cells produce antibodies.
Explanation:
* B lymphocytes are immune cells responsible for antibody production.
* Upon encountering an antigen, B lymphocytes differentiate into lymphoblasts, then plasmablasts, and finally plasma cells.
* Plasma cells produce specific antibodies to fight that antigen.
Note:
* B lymphocytes also play a role in creating memory cells, helping the body remember and respond quickly to previously encountered antigens.
14. T lymphocytes do not have the characteristic of
B. Directly stimulating antibody production
Explanation:
* T lymphocytes are responsible for cell-mediated immunity, they do not directly produce antibodies.
* T lymphocytes are divided into various types, each with a specific function in killing virus-infected cells, cancer cells, foreign cells…
* T lymphocytes can activate B lymphocytes to produce antibodies through chemical signals.
Note:
* T lymphocytes are an essential part of the immune system, protecting the body from harmful agents.
15. Platelets: Have a normal count of 200-300 G/l of blood.
A. True
Explanation:
* Platelets are small, non-nucleated blood cells that play a crucial role in blood clotting.
* The normal platelet count in peripheral blood is 150,000 to 450,000/mm3 (equivalent to 150-450 G/l).
Note:
* Decreased or increased platelet count can be a sign of certain medical conditions.
* For example, decreased platelets can be caused by immune thrombocytopenia, bone marrow failure… Increased platelets can be caused by polycythemia vera…
16. Platelets: Contain thrombosthenin, actin, and myosin that contract the blood clot.
A. True
Explanation:
* Platelets contain thrombosthenin, actin, and myosin, proteins that play a role in blood clot contraction.
* When platelets bind to a wound, they release thrombosthenin, actin, and myosin, causing blood clot contraction, effectively stopping bleeding.
Note:
* Blood clot contraction is a complex process involving various clotting factors.
17. Vasoconstriction: Stronger when the blood vessel damage is greater.
A. True
Explanation:
* Vasoconstriction is the body’s natural response to stop bleeding.
* When a blood vessel is damaged, receptors on the vessel wall release chemical mediators such as serotonin, norepinephrine… causing vasoconstriction, reducing blood loss.
* The stronger the vasoconstriction, the greater the blood vessel damage.
Note:
* Vasoconstriction is one of the first stages of the hemostasis process.
18. The formation of a platelet plug: Will completely seal any wound and stop the bleeding.
B. False
Explanation:
* The formation of a platelet plug is an essential part of hemostasis, but it cannot completely seal any wound and stop bleeding completely.
* The platelet plug can only seal small wounds, while larger wounds require other methods to control bleeding, such as bandages, stitches…
Note:
* The platelet plug is a thin membrane that cannot withstand high blood pressure.
* The platelet plug is only the first stage of hemostasis, followed by the clotting process.
19. The formation of a platelet plug: Will be prolonged when the platelet count is below 150 G/l of blood.
A. True
Explanation:
* A platelet count below 150,000/mm3 (equivalent to 150 G/l) will reduce the ability to form a platelet plug, prolonging the bleeding time.
* This condition can lead to easy bleeding, even uncontrollable bleeding.
Note:
* Decreased platelets are a symptom of many medical conditions and need to be diagnosed and treated promptly.
20. The clotting process: Normal clotting time is 7 minutes.
A. True
Explanation:
* Normal clotting time is 5 to 10 minutes.
* Clotting time can vary from person to person, depending on factors such as: age, health, medication…
Note:
* Prolonged clotting time can be a sign of certain medical conditions such as: vitamin K deficiency, liver disease, blood disorders…
21. One of the following diseases is caused by a deficiency of factor VIII:
A. Hemophilia A.
Explanation:
* Hemophilia is a genetic disorder that causes a bleeding disorder due to a deficiency of clotting factors.
* Hemophilia A is the most common type of hemophilia, caused by a deficiency of factor VIII.
* Hemophilia B is caused by a deficiency of factor IX.
Note:
* Hemophilia is a serious medical condition that can lead to severe bleeding and life-threatening complications.
22. Anticoagulants: Heparin has an anticoagulant effect in vivo and in vitro by directly inactivating clotting factors.
B. False
Explanation:
* Heparin is an anticoagulant that has an effect in vivo (in the body) and in vitro (in a test tube).
* Heparin does not directly inactivate clotting factors, but it acts on antithrombin III (ATIII), increasing its ability to inhibit thrombin and other clotting factors.
Note:
* Heparin is used to prevent and treat thrombosis.
23. Anticoagulants: Coumarin is only used for anticoagulation in a test tube.
B. False
Explanation:
* Coumarin is an anticoagulant that has an effect in vivo (in the body).
* Coumarin inhibits the liver’s synthesis of vitamin K-dependent clotting factors, reducing clotting ability.
Note:
* Coumarin is used to prevent and treat deep vein thrombosis.
24. Anticoagulants: EDTA is an antithrombotic agent in the body by reducing the concentration of Ca2+ ions in the blood.
B. False
Explanation:
* EDTA is an in vitro (in a test tube) anticoagulant, it does not have an anticoagulant effect in the body.
* EDTA is a substance that binds to Ca2+ ions, reducing the concentration of Ca2+ in the blood, thereby preventing blood clotting in a test tube.
Note:
* EDTA is used in blood tests to prevent blood clotting.
25. Anticoagulants: Thrombomodulin inhibits thrombin, thus having a strong anticoagulant effect.
A. True
Explanation:
* Thrombomodulin is a protein produced by blood vessel endothelial cells, it inhibits thrombin.
* Thrombomodulin binds to thrombin to form the thrombomodulin-thrombin complex, which then activates protein C, a strong anticoagulant protein.
Note:
* Thrombomodulin is an essential part of the body’s natural anticoagulant system.
26. Heparin has the effect of:
D. Inhibiting thrombin.
Explanation:
* Heparin is an anticoagulant that inhibits thrombin.
* Heparin binds to antithrombin III (ATIII), enhancing the activity of ATIII, thereby inhibiting thrombin.
Note:
* Heparin also inhibits other clotting factors, but its effect on inhibiting thrombin is strongest.
27. The mechanism of action of dicoumarin is:
D. Inhibiting the liver’s synthesis of factors II, VII, IX, X.
Explanation:
* Dicoumarin is an indirect anticoagulant, it inhibits the liver’s synthesis of vitamin K-dependent clotting factors, including: factors II, VII, IX, X.
Note:
* Dicoumarin is used to prevent and treat deep vein thrombosis and arterial thrombosis.
28. Which of the following substances does not have an anticoagulant effect?
D. Bradykinin
Explanation:
* Bradykinin is an inflammatory mediator, it does not have an anticoagulant effect.
* Bradykinin has the effects of vasodilation, increased vascular permeability, pain…
Note:
* Other substances such as: citrate, EDTA, heparin, coumarin all have anticoagulant effects.
29. To evaluate the preliminary stage of hemostasis, clinicians often use the following tests, except:
D. Quantifying each clotting factor.
Explanation:
* Tests used to evaluate the preliminary stage of hemostasis include:
* Tourniquet test: Evaluates vasoconstriction ability.
* Bleeding time determination: Evaluates platelet function.
* Direct platelet count: Evaluates platelet count.
* Platelet aggregation measurement: Evaluates platelet function.
* Quantifying each clotting factor is a more complex test used to diagnose bleeding disorders.
Note:
* Tests evaluating the preliminary stage of hemostasis help clinicians detect early bleeding disorders and provide timely treatment.
Conclusion:
The above article has provided basic knowledge about blood physiology, including: the function of blood components, the clotting process, factors affecting clotting, anticoagulants, and some tests evaluating the preliminary stage of hemostasis. Hopefully, this article will help you better understand the crucial role of blood in the body and help you protect your health.
Leave a Reply