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 bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Which of the following molecule is incorrectly paired with its action ?

  1. Interleukin I-stimulates division of helper T-cells

  2. Interferon-helps neighbouring cells to resist viral infection

  3. Histamine-fights allergic reactions

  4. Lysozyme-attacks bacterial cell walls
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A- IL-1α is produced mainly by activated macrophages, as well as neutrophils, epithelial cells, and endothelial cells. It possesses metabolic, physiological, haematopoietic activities, and plays one of the central roles in the regulation of the immune responses. It binds to the interleukin-1 receptor.

B- Interferons (IFNs) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses.
C- When they leave the mast cells, histamines boost blood flow in the area of your body the allergen affected. This causes inflammation, which lets other chemicals from your immune system step in to do repair work.
D- Lysozyme is capable of breaking the chemical bonds in the outer cell wall of the bacteria. Bacterial cell walls contain a layer of peptidoglycan, which is the specific site that lysozyme targets. The peptidoglycan layer contains alternating molecules called N-acetylglucosamine and N-acetylmuramic acid. 

So, the correct option is 'Option C'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Read the following statements and select the correct option.
(A) Thymosins plays a major role in differentiation of T lymphocyte which provides cell-mediated immunity.
(B) Thymosins promote the production of antibodies to provide humoral immunity.

  1. Both (A) and (B) are true

  2. (A) is false but (B) is true

  3. Both (A) and (B) are false

  4. (A) is true but (B) is false
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Thymosins are proteins present in animal tissues. They have diverse biological activities. It is serrated by the thymus gland and it is important because it stimulates the development of T.lymphocytes also known as killer T.blood cells. It also functions in the immune system to recognize foreign antigens on the surface of cells.

so,the correct option is 'Both(A) and (B) are true'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

which of the following are necessary for the production of maximal humoral response upon initial exposure to a protein antigen?

  1. B lymphocytes only

  2. T lymphocytes only

  3. B lymphocytes and dendritic cells only

  4. B lymphocytes and T lymphocytes only

  5. B lymphocytes , T lymphocytes and dendritic cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

B cells, otherwise called B lymphocytes, are a sort of white platelet of the lymphocyte subtype. They work in the humoral insusceptibility segment of the versatile safe framework by emitting antibodies. 

So, the correct option is 'B lymphocytes only'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Immunocompetence refers to the

  1. ability of the immune system to distinguish self from non-self

  2. differentiation, depending on location of lymphocytes into B- or T-cells

  3. development of receptors on B- and T-cells that are specific for one particular antigenic determinant

  4. ability of helper T-cells to recognize the major histocompatibility complex
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Immunocompetence is the ability of the body to produce a normal immune response following exposure to an antigen. Immunocompetence is the opposite of immunodeficiency.

So, the correct option is 'Development of receptors on B- and T cells that are specific for one particular antigenic determinant'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Primary and secondary immune response are carried out with the help of 

  1. B-Lymphocytes

  2. T-Lymphocytes

  3. Antiviral Proteins

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The primary immune response can be described as the first response of our body system to a newly introduced foreign agent, while the secondary immune response is defined as an intensified immune response to this previously exposed antigen. The primary and secondary immune response is carried out by following two types of lymphocytes;
1)B-Lymphocytes: responsible for the production of antibodies in our blood. the type of antibodies is IgA. IgD, IgE, IgG, IgM.
2)T-Lymphocytes: These are mediators cell-mediated immunity.
So, the correct answer is 'Option D- Both A and B'.
Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

The major difference between humoral immunity and cell-mediated immunity is that:

  1. humoral immunity is non-specific, whereas cell-mediated immunity is specific for particular antigens

  2. the agents of humoral immunity are carried in the bloodstream, whereas the cells of the latter are concentrated in lymph nodes

  3. humoral immunity cannot function independently; it is always activated by cell-mediated immunity

  4. humoral immunity acts against free-floating antigens, whereas cell-mediated immunity works against pathogens that. have entered body cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The immune system has two divisions-humoral immunity and cell-mediated immunity. The humoral immunity protects against extracellular pathogens while the cell-mediated immunity protects against intracellular pathogens.

so, the correct option is 'humoral immunity acts against free-floating antigens, whereas cell-mediated immunity works against pathogens that have entered body cells'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

The cells that actually release antibodies are

  1. Helper T-cells

  2. Cytotoxic T-cells

  3. Plasma cells

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

Activated B cells differentiate into either antibody-producing cells called plasma cells that secrete soluble antibody or memory cells that survive in the body for years afterwards in order to allow the immune system to remember an antigen and respond faster upon future exposures.

So, the correct option is 'Plasma cells'.

Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Control of the activated complement components results from

  1. Agglutination

  2. Immune adherence

  3. Instability and inactivation of some of these components

  4. Mobility of phagocytes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The activity of complement components is modulated by a system of regulatory proteins that prevent tissues damage as a result of inadvertent binding of activated complement components to host cells or spontaneous activation of complement components in plasma.

So, the correct option is 'instability and inactivation of some of these components'.

Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

Lysis of foreign cells is mediated through

  1. IgM only

  2. IgA only

  3. IgM and IgG

  4. IgD and IgE
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Immunoglobulin M (IgM) is one of several forms of the antibody that are produced by vertebrates. IgM is the largest antibody, and it is the first antibody to appear in the response to initial exposure to an antigen. IgM can bind to complement component and activate the classical pathway, leading to opsonization of antigens and cytolysis (lysis of foreign cells).
  • IgG is the most common type of antibody found in blood circulation. IgG molecules are created and released by plasma B cells. Coating of IgG on pathogen surfaces (known as opsonization) allows their recognition and ingestion by phagocytic immune cells leading to the lysis of foreign cells.
So, the correct answer is 'IgM and IgG'.
Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

Antibodies are formed by

  1. T-cells

  2. Monocytes

  3. Phagocytes

  4. B-cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Antibody are produced by B-lymphocytes. The plasma cell /plasma B cells/effector B cell are white blood cells that secrete large volumes of antibodies. Plasma cell originates in the bone marrow.B cell differentiate into a plasma cell that produces antibody molecules. These are transported by the blood plasma and the lymphatic system. Once these are released into the blood and lymph, these antibody molecules bind to the target antigen and initiate its neutralization or destruction.

So, the correct answer is 'B-cells'.

Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

Antibodies are complex 

  1. Lipoproteins

  2. Steroids

  3. Prostaglandins

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

Immunoglobulin also known as antibodies are glycoprotein molecules produced by plasma cells (white blood cells). They act as a critical part of the immune response by specifically recognizing and binding to particular antigens, such as bacteria or viruses and help in their destruction.The antibody immune response is highly complex and exceedingly specific. Hence, antibodies are complex glycoproteins.

So,the correct answer is 'Glycoproteins'.

Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

Immunoglobulins (antibodies) are basically

  1. Lipoproteins

  2. Phospholipids

  3. Glycoproteins

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

Immunoglobulins, also known as antibodies, are glycoprotein molecules produced by plasma cells (white blood cells). They act as a critical part of the immune response by specifically recognising and binding to particular antigens, such as bacteria or viruses, and aiding in their destruction. So, the correct option is 'Glycoproteins'

Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

Which statement is correct?

  1. Antibodies are formed by mast cells

  2. B-lymphocytes are matured in thymus

  3. Histamine acts as inflamatory mediator

  4. CMI is mediated by B-lymphocytes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mast cells are coated with IgE, which is produced by plasma cells (the antibody-producing cells of the immune system). IgE antibodies are typically specific to one particular antigen. In allergic reactions, mast cells remain inactive until an allergen binds to IgE already coated upon the cell.

So, the correct option is 'Antibodies are formed by mast cells'.

Multiple choice bio-chemistry diseases and immunity antibodies antibodies and antitoxin antigen and antibody

................  is associated with allergic reactions

  1. IgE

  2. IgG

  3. IgA

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

Antibodies are the immunoglobulins which are produced in response to the antigen. The immunoglobulin E antibodies or IgE binds to an allergen and trigger the release of inflammatory chemicals such as histamine.
Therefore, the correct answer is option A.