Biology

Human Immunity and Blood

2,051 Questions

Human immunity and blood questions cover the physiological mechanisms protecting the body against diseases and the components of blood. Topics include blood groups, cell mediated immunity, monoclonal antibodies, and blood coagulation. These biology topics frequently appear in general science sections of competitive exams.

Blood groupsCell mediated immunityMonoclonal antibodiesBlood coagulationCancer immunology

Human Immunity and Blood Questions

Multiple choice

Which of the following is NOT a type of inflammatory cell?

  1. Neutrophils

  2. Macrophages

  3. Lymphocytes

  4. Eosinophils
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Lymphocytes are not inflammatory cells in the strict sense. They are part of the adaptive immune system and play a role in specific immune responses, such as antibody production and cell-mediated immunity.

Multiple choice

What is the role of macrophages in the inflammatory response?

  1. They phagocytose foreign particles and cellular debris

  2. They release histamine and serotonin

  3. They produce antibodies

  4. They activate complement proteins
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Macrophages are phagocytic cells that engulf and destroy foreign particles, including bacteria, cellular debris, and apoptotic cells. They also secrete cytokines and other inflammatory mediators.

Multiple choice

Which cytokine is primarily responsible for the fever associated with inflammation?

  1. Interleukin-1 (IL-1)

  2. Tumor necrosis factor-alpha (TNF-alpha)

  3. Interleukin-6 (IL-6)

  4. Interferon-gamma (IFN-gamma)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Interleukin-1 (IL-1) is a potent pyrogen, meaning it can induce fever. It acts on the hypothalamus, causing an increase in body temperature.

Multiple choice

What is the role of complement proteins in the inflammatory response?

  1. They promote vasodilation and increased vascular permeability

  2. They inhibit the release of inflammatory cytokines

  3. They stimulate the production of antibodies

  4. They lyse foreign cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Complement proteins are a group of proteins that work together to lyse foreign cells, such as bacteria and viruses. They also promote inflammation by generating anaphylatoxins, which are potent inflammatory mediators.

Multiple choice

What is the role of leukotrienes in the inflammatory response?

  1. They promote vasodilation and increased vascular permeability

  2. They inhibit the release of inflammatory cytokines

  3. They stimulate the production of antibodies

  4. They attract neutrophils to the site of inflammation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Leukotrienes are lipid mediators that attract neutrophils to the site of inflammation. They also promote bronchoconstriction and mucus production in the airways.

Multiple choice

Which of the following is NOT a type of inflammatory cell?

  1. Neutrophils

  2. Macrophages

  3. Eosinophils

  4. Basophils
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Basophils are not inflammatory cells in the strict sense. They are involved in allergic reactions and release histamine and other inflammatory mediators.

Multiple choice

What is the most common type of blood transfusion?

  1. Whole blood transfusion

  2. Red blood cell transfusion

  3. Platelet transfusion

  4. Plasma transfusion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Red blood cell transfusions are the most frequently performed type, as they are used to treat conditions such as anemia and blood loss.

Multiple choice

What is the ABO blood group system?

  1. A classification system based on the presence or absence of A and B antigens on red blood cells

  2. A classification system based on the presence or absence of Rh factor on red blood cells

  3. A classification system based on the presence or absence of both A and B antigens and Rh factor on red blood cells

  4. A classification system based on the presence or absence of plasma proteins
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The ABO blood group system classifies blood into four main groups: A, B, AB, and O, based on the presence or absence of A and B antigens on the surface of red blood cells.

Multiple choice

What is the Rh factor?

  1. A protein found on the surface of red blood cells

  2. A protein found in plasma

  3. A protein found in white blood cells

  4. A protein found in platelets
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Rh factor is a protein found on the surface of red blood cells. Individuals who have the Rh factor are Rh-positive, while those who lack it are Rh-negative.

Multiple choice

What is the significance of blood type compatibility in blood transfusions?

  1. To prevent immune reactions and transfusion complications

  2. To ensure the proper functioning of transfused blood cells

  3. To maintain blood pressure levels

  4. To regulate blood clotting
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Blood type compatibility is crucial in blood transfusions to prevent immune reactions and transfusion complications. Incompatible blood transfusions can lead to hemolytic reactions, where transfused red blood cells are destroyed by the recipient's immune system.

Multiple choice

What is the role of cross-matching in blood transfusions?

  1. To determine the compatibility of donor and recipient blood

  2. To measure the volume of blood to be transfused

  3. To check for the presence of infections in the donor's blood

  4. To monitor the patient's vital signs during the transfusion
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cross-matching is a laboratory procedure performed before a blood transfusion to ensure the compatibility of donor and recipient blood. It involves testing the recipient's serum against the donor's red blood cells to detect any potential immune reactions.

Multiple choice

What are the potential risks and complications associated with blood transfusions?

  1. Immune reactions, such as hemolytic transfusion reactions

  2. Transfusion-related infections

  3. Circulatory overload

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Blood transfusions carry potential risks and complications, including immune reactions (e.g., hemolytic transfusion reactions), transfusion-related infections (e.g., hepatitis, HIV), and circulatory overload (excessive fluid volume in the bloodstream).

Multiple choice

What are the criteria for selecting a suitable blood donor?

  1. Healthy individuals between the ages of 18 and 65

  2. Individuals with a history of blood transfusions

  3. Individuals with certain medical conditions, such as diabetes or heart disease

  4. Individuals who have recently taken certain medications
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Suitable blood donors are typically healthy individuals between the ages of 18 and 65 who meet specific health and lifestyle criteria, such as having a normal blood pressure, hemoglobin level, and no history of certain medical conditions or recent medication use that may affect the safety of the blood donation.

Multiple choice

What is the process of leukoreduction in blood transfusions?

  1. Removing white blood cells from donated blood

  2. Adding white blood cells to donated blood

  3. Separating red blood cells from plasma

  4. Mixing different blood types together
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Leukoreduction is the process of removing white blood cells from donated blood. This is done to reduce the risk of transfusion-related complications, such as febrile non-hemolytic transfusion reactions and transfusion-associated graft-versus-host disease.

Multiple choice

Which organ is responsible for producing red blood cells?

  1. Bone marrow

  2. Liver

  3. Kidneys

  4. Spleen
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bone marrow is a soft tissue found inside bones that produces red blood cells, white blood cells, and platelets.