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 a potential complication of blood transfusion?

  1. Hemolytic reaction

  2. Anaphylactic reaction

  3. Transfusion-related acute lung injury (TRALI)

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

Hemolytic reaction, anaphylactic reaction, and transfusion-related acute lung injury (TRALI) are all potential complications of blood transfusion.

Multiple choice

What is the role of white blood cells in the immune system?

  1. Producing antibodies

  2. Digesting food

  3. Transporting oxygen

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

White blood cells, also known as leukocytes, play a crucial role in the immune system by producing antibodies that recognize and attack foreign invaders.

Multiple choice

Which type of T cell is responsible for recognizing and killing infected cells?

  1. Cytotoxic T cells (Tc cells)

  2. Helper T cells (Th cells)

  3. Regulatory T cells (Treg cells)

  4. Memory T cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cytotoxic T cells, also known as killer T cells, are responsible for recognizing and eliminating infected cells or cancerous cells by releasing cytotoxic molecules that induce cell death.

Multiple choice

What is the role of Helper T cells (Th cells) in the immune response?

  1. Directly killing infected cells

  2. Producing antibodies

  3. Activating other immune cells

  4. Suppressing immune responses
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Helper T cells play a crucial role in coordinating immune responses by releasing cytokines that activate other immune cells, such as cytotoxic T cells, B cells, and macrophages.

Multiple choice

What is the process by which T cells become activated?

  1. Antigen presentation

  2. Cytokine signaling

  3. Cell-cell contact

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

T cell activation is a complex process that involves antigen presentation by antigen-presenting cells (APCs), cytokine signaling, and cell-cell contact between T cells and APCs.

Multiple choice

Which molecule is responsible for presenting antigens to T cells?

  1. MHC class I molecules

  2. MHC class II molecules

  3. TCR (T cell receptor)

  4. CD8
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

Antigens are presented to T cells by MHC (major histocompatibility complex) molecules. MHC class I molecules present antigens to CD8+ T cells, while MHC class II molecules present antigens to CD4+ T cells.

Multiple choice

What is the role of the TCR (T cell receptor) in T cell activation?

  1. Recognizing antigens

  2. Binding to MHC molecules

  3. Transducing signals into the cell

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

The TCR is responsible for recognizing antigens presented by MHC molecules, binding to them, and transducing signals into the T cell, leading to its activation.

Multiple choice

What are the two main subsets of CD4+ Helper T cells?

  1. Th1 and Th2 cells

  2. Th1 and Th17 cells

  3. Th2 and Th17 cells

  4. Th1, Th2, and Th17 cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

CD4+ Helper T cells can be divided into two main subsets: Th1 cells and Th2 cells. Th1 cells are involved in cell-mediated immunity, while Th2 cells are involved in humoral immunity.

Multiple choice

What is the role of Th1 cells in the immune response?

  1. Producing antibodies

  2. Killing infected cells

  3. Activating macrophages

  4. Suppressing immune responses
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Th1 cells play a crucial role in cell-mediated immunity by releasing cytokines that activate macrophages and other phagocytic cells, enhancing their ability to kill intracellular pathogens.

Multiple choice

What is the role of Th2 cells in the immune response?

  1. Killing infected cells

  2. Producing antibodies

  3. Activating macrophages

  4. Suppressing immune responses
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Th2 cells play a critical role in humoral immunity by releasing cytokines that stimulate B cells to differentiate into antibody-producing plasma cells, leading to the production of antibodies against pathogens.

Multiple choice

What is the role of Th17 cells in the immune response?

  1. Producing antibodies

  2. Killing infected cells

  3. Activating macrophages

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

Th17 cells are involved in promoting inflammation and immune responses against extracellular bacteria and fungi. They release cytokines that recruit neutrophils and other inflammatory cells to the site of infection.

Multiple choice

What is the process by which T cells differentiate into effector T cells?

  1. Activation

  2. Proliferation

  3. Differentiation

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

T cell differentiation into effector T cells involves a series of steps, including activation, proliferation, and differentiation into specific effector T cell subsets, such as cytotoxic T cells, helper T cells, and regulatory T cells.

Multiple choice

What are the different types of effector T cells?

  1. Cytotoxic T cells (Tc cells)

  2. Helper T cells (Th cells)

  3. Regulatory T cells (Treg cells)

  4. Memory T cells

  5. All of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Effector T cells include cytotoxic T cells (Tc cells), helper T cells (Th cells), regulatory T cells (Treg cells), and memory T cells. Each subset has a distinct role in the immune response.

Multiple choice

What is the role of cytokines in T cell activation and differentiation?

  1. Activating T cells

  2. Promoting proliferation

  3. Inducing differentiation

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

Cytokines play a crucial role in T cell activation, proliferation, and differentiation. They are produced by various immune cells and act as signaling molecules that regulate T cell responses.

Multiple choice

What is the most common type of Sickle Cell Anemia?

  1. HbSS

  2. HbSC

  3. HbSβ-thalassemia

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

HbSS is the most common type of Sickle Cell Anemia, characterized by the presence of two copies of the sickle cell gene (βS).