Dna - history and structure - class-X

Interferons (IFNs) are proteins made and released by virally infected host cells in response to the presence of pathogens, such as viruses, bacteria, parasites, or tumor cells to protect the adjacent cells from the infection by interfering the DNA replication of the virus in the host cell. So, the correct answer is option B.

Interferons are produced by the body cells as a defensive response to viruses. These belong to the group known as cytokines. Type II interferon is secreted only by natural killer cells and T lymphocytes, its main purpose is to signal the immune system to respond to infectious agents or cancerous growth. So, the correct answer is option A.

Interferons (IFNs) belong to the large class of proteins known as cytokines, molecules used for communication between cells to trigger the protective defences of the immune system that help eradicate pathogens. Interferons are named for their ability to interfere with viral replication by protecting cells from virus infections. 

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines).
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence Interferon is the protein that protects unattacked cells from viruses.
• So, the correct answer is 'Protects unattacked cells from virus'.
  

• The first interferon was discovered in 1957 by Alick Isaacs and Jean Lindenmann. During their investigation, the two scientists found that virus-infected cells secrete a special protein that causes both infected and noninfected cells to produce other proteins that prevent viruses from replicating. Hence interferons were discovered by Isaac and Lindemann.
• So, the correct answer is 'Isaac and Lindemann'.

Interferons are proteins released by host cells in response to the presence of viruses, not bacteria. Furthermore, they do not stimulate inflammation; they inhibit viral replication in neighboring cells.

Interferons (IFNs) are a group of signalling proteins made and released by host cells in response to the presence of several viruses. A virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defences. Interferons are named for their ability to "interfere" with viral replication (multiplication) by protecting cells from virus infections. Hence, interferons are used in the treatment of viral infections such as influenza. Influenza, commonly known as the flu is an infectious disease caused by an influenza virus.

Interferons are a group of proteins called cytokines, produced by animal white blood cells, fibroblasts or T-cells as part of the immune response to a viral infection or other immune trigger. The name of proteins comes from their ability to interfere with the replication of new virus particles.
Interferons do not directly kill viral or cancerous cells. They boost the immune system response and reduce the growth of cancer cells by regulating the action of several genes that control the secretion of numerous cellular proteins that affect the growth.
The virus infected cells secrete a special protein that causes both infected and non infected cells, to produce other proteins that prevent viruses from replicating and protecting the non infected cells.
So the correct option is 'All of the above'.

Interferons are proteinaceous in nature. These are released by the virally infected and dying cells as a response to the attack. Interferons are named for their ability to interfere with viral replication by protecting cells from virus infections. It induces antiviral mechanism in the neighbouring cells. 

• Lymphokines are a typer of cytokines which are secreted by the lymphocytes (immune cell).
• They are a type of small proteins secreted by cells of the immune system that helps in signalling and effects the behaviour of the neighbouring cells.
• Lymphokines attract the other cells of the immune system such as macrophages and other lymphocytes to an infected site and activate them to prepare for an immune response. 
• They are secreted by the T-lymphocytes.
• Lymphokines help the B- lymphocyte cells to produce antibodies.
• Interferon is a lymphokine secreted by the T-lymphocytes which are responsible for innate and adaptive immunity against viruses, few bacteria and protozoa.
• It is known as Interferon-gamma (IFNγ).
• It inhibits viral replication by its immunostimulatory and immunomodulatory effects.
  
• So, the correct answer is 'Interferon'.

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines). These interferons restrict the viral multiplication in the body.
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence interferon acts against virus.
• So,the correct answer is 'Virus'.

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines).
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence Interferon suppresses the pathogenic activity of Viruses.
• So, the correct answer is 'Viruses'.

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines).
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence a cell coded protein formed in response to infection with most animal viruses is interferon.
• So, the correct answer is 'Interferon'.

Penicillin-antibiotic.

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines). Interferons suppress the viral multiplication.
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence interferons suppresses the pathogenicity of viruses.
• So, the correct answer is 'Viruses'.

• Interferons are a group of signalling proteins made and released by host cells in response to the presence of several viruses. Generally, a virus-infected cell will release interferons causing nearby cells to make their anti-viral defences.
• A paratope also called an antigen-binding site or Fab. It is a part of an antibody which recognizes and binds to an antigen. It is a small region of the antibody containing the antibody's heavy and light chains.
• Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that were first seen to be expressed by white blood cells (leukocytes).
• Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological function in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Histamine is involved in the inflammatory response and has a central role as a mediator of itching.
• So, the correct answer is 'a-iii,b-i,c-iv,d-ii'.

Interferons are glycoproteins produced by cells in response to viral infections and are now produced using recombinant DNA technology (genetic engineering) for therapeutic use.

Interferon is the name given to a group of proteins known primarily for their role in inhibiting viral infections and in stimulating the entire immune system to fight disease. Research has also shown that these proteins play numerous roles in regulating many kinds of cell functions. Interferons can promote or hinder the ability of some cells to differentiate, that is, to become specialized in their function. They can inhibit cell division, which is one reason why they hold promise for stopping cancer growth. Recent studies have also found that one interferon may play an important role in the early biological processes of pregnancy. Although once thought to be a potential cure-all for a number of viral diseases and cancers, subsequent research has shown that interferons are much more limited in their potential. 

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. Interferons are a group of proteins called cytokines produced by white blood cells, fibroblasts, or T-cells as part of an immune response to a viral infection or other immune trigger. The name of the proteins comes from their ability to interfere with the production of new virus particles.

Interferon was named for its ability to interfere with viral proliferation. The various forms of interferon are the body’s most rapidly produced and important defense against viruses. Interferons can also combat bacterial and parasitic infections, inhibit cell division, and promote or impede the differentiation of cells. They are produced by all vertebrate animals and possibly by some invertebrates as well.

Interferons are categorized as cytokines, small proteins that are involved in intercellular signaling. Interferon is secreted by cells in response to stimulation by a virus or other foreign substance, but it does not directly inhibit the virus’s multiplication. Rather, it stimulates the infected cells and those nearby to produce proteins that prevent the virus from replicating within them.

So, the correct option is 'False'.

Interferons are a group of proteins called cytokines produced by WBC, fibroblasts, or T-cells as part of an immune response to a viral infection or other immune triggers. Interferons are proteinaceous in nature but not glycolipid in nature, thus interferon which prevents viral multiplication are protein particles.

Interferons are a group of signaling proteins made and released by host cells in response to the presence of pathogens, such as viruses, bacteria, parasites, or tumour cells. They are a group of glycoproteins, produced by the immune system, that prevent viral replication in infected cells.