Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

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

A molecule that produces an immune response is

  1. Antigen

  2. Antibody

  3. Carcinogen

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

An antigen is a foreign substance which produces an immune response and is specifically bound to antibodies. Each antibody is specifically produced by the immune system to match an antigen after cells in the immune system come into contact with it, this allows a precise identification or matching of the antigen. Antigens are usually proteins, peptides and polysaccharides which elicit an immune response.

So, the correct answer is 'Antigen'.

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

Cells of immune system that cause pore formation in the antigen are

  1. Helper T-cells

  2. Killer T-cells

  3. Suppressor T-cells

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

A cytotoxic T-cell, also known as Killer T-cells is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways. When killer T-cells are exposed to antigens, they release the cytotoxins perforin, granzymes, and granulysin. Perforins and granzymes causes pore formation in the antigen which causes the intracellular content of antigen to leak out resulting in cell death.

So, the correct answer is 'Killer T-cells'.

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

Memory cells are formed from 

  1. Erythropoietic stem cells

  2. Monocytes

  3. T-lymphocytes

  4. B-lymphocytes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Memory cells are formed from T-lymphocytes because memory T cells have the ability to recognized specific antigen. They will activate a stronger and faster immune response after they come across the same antigen again

So, the correct answer is 'T-lymphocytes'

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

Surgical removal of thymus of a new born shall results in failure to produce

  1. Monocytes

  2. B-lymphocytes

  3. T-lymphocytes

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

The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, T cells mature. T cells are critical to the adaptive immune system, where the body adapts specifically to foreign invaders. The thymus is the largest and most active during the neonatal and pre-adolescent periods.  Surgical removal of the thymus results in immunodeficiency because T- cells do not undergo maturation and this results in suppression of the immune system. 

So, the correct answer is 'T-lymphocytes'.

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

Humoral immunity is due to 

  1. T-lymophocytes

  2. L-lymophocytes

  3. P-lymophocytes

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

Humoral immunity is a type of immunity which is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. Humoral immunity is so named because it involves substances found in the humour or body fluids. It involves B-lymphocytes or plasma cells and is often known as antibody-mediated immunity.

So, the correct answer is 'B-lymphocytes or plasma cells'.

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

Helper cells are distinguished from cytotoxic T-cells by the presence of

  1. CD 2

  2. CD 4

  3. CD 3

  4. IL-2 receptor
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • T-cells are a type of white blood cell that plays a central role in cell-mediated immunity. 
  • T-helper cell assists other white blood cells in immunologic processes, including maturation of B cells into plasma cells and memory B cells and activation of cytotoxic T cells and macrophages. These cells are also known as CD4+ T cells because they express the CD4 glycoprotein on their surfaces.
  • Cytotoxic T-cells destroy virus-infected cells and tumour cells and are also implicated in transplant rejection. These cells are also known as CD8+ T cells since they express the CD8 glycoprotein at their surfaces.
  • So, the correct answer is 'CD 4'.
Multiple choice bio-chemistry immunity and blood groups active and passive immunity acquired immunity innate and acquired immunity

Immune system is made up of 

  1. Humoral system

  2. Humoral and fibrous systems

  3. Humoral and cell mediated systems

  4. Antigen induced antibodies
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

  • The immune system is a host defence system comprising many biological structures and processes within an organism that protects against disease.  The immune system can be classified into subsystems such as the innate immune system and the adaptive immune system, or humoral immunity and cell-mediated immunity. 
  • Humoral immunity is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides.
  • Cell-mediated immunity is an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.
So, the correct answer is 'Humoral and cell-mediated systems'.

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

T-cells respond to pathogens by producing 

  1. Killer T-cells

  2. Helper T-cells

  3. Supressor T-cells and memory cells

  4. Killer T-cells, helper T-cells and supressor T-cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

T cell is a type of WBC that plays a central role in cell-mediated immunity. They are called T cells because they mature in the thymus from thymocytes. T cells kill the pathogen by producing - 

  • T-helper cells - It causes maturation of B cells into plasma cells and memory B cells, and activation of cytotoxic T cells and macrophages.
  • Killer T-cells - They destroy virus-infected cells and tumour cells, and are also implicated in transplant rejection.
  • Suppressor T-cells - They are crucial for the maintenance of immunological tolerance. Their major role is to stop T cell-mediated immunity toward the end of an immune reaction.
So, the correct answer is 'Killer T-cells, helper T-cells and suppressor T-cells'.

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

What is true about T-lymphocytes in mammals : -

  1. There are three main types-cytotoxic T-cells, helper T-cells and suppressor T-cells

  2. These originate in lymphoid tissues

  3. They scavenge damaged cells and cellular debris

  4. These are produced in thyroid
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
T cells account for about 80% of all lymphocytes. They are named T cells because they mature in the thymus, a gland found in the chest. There are three types of T cell lymphocytes:
  • Cytotoxic T cell
  •  Suppressor T cell
  •  Helper T cell
Helper T cells are arguably the most important cells in adaptive immunity, as they are required for almost all adaptive immune responses. They not only help activate B cells to secrete antibodies and macrophages to destroy ingested microbes, but they also help activate cytotoxic T cells to kill infected target cells. A cytotoxic T cell is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways. The regulatory T cells formerly known as suppressor T cells are a subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease.

So, the correct answer is 'There are three main types-cytotoxic T-cells, helper T-cells, and suppressor T-cells'.