Microbiology with Diseases by Taxonomy Chapter 18 Answers

Microbiology with Diseases by Taxonomy Chapter 18 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1CM
Immediate hypersensitivity:
Explanation
Type I hypersensitivity gives rise to allergies. Allergies result when allergens bind to IgE molecules that are already bound to mast cells and basophils. It causes the sensitized cells to degranulate and release histamines. As a result, it produces localized allergic reactions with clinical syndromes. The symptoms include hay fever, asthma and urticarial. Antihistamines are administered for asthma patients. In systemic allergic reactions, anaphylactic shock may occur. The specific treatment for anaphylaxis is epinephrine.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1CT
The advantages of an individual that gain in making class E antibodies (IgE):
Explanation
IgE antibodies provide immunity against parasitic worms and protozoan parasite. Moreover, an allergen that triggers to IgE antibodies attaches to antigen binding sites. In addition, IgE antibodies are present on the mast cells and basophils, producing histamines and release into neighborhood.
Therefore, people exposed to internal parasites benefit from IgE antibody production. In rarely infected person, IgE antibodies are produced at low levels, in blood serum.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1L
Graft types are named according to the relation between donor and the recipient. A graft is called an autograft when tissues are moved to a different location, within the same individual. A best example for autograft includes grafting of skin from one area of the body to another to cover a burns (or) use of a leg vein to bypass blocked coronary arteries.
Isografts are grafts transplanted between genetically identical individuals like siblings (or) clones. The MHC proteins are identical in these individuals. Thus Isografts are not rejected since they do not trigger immune response.
Allografts are grafts transplanted between genetically distinct members of the same species. The MHC proteins are not same in donor and recipient, it triggers strong type IV hypersensitivity reaction, which results in graft rejection.
Xenografts are grafts transplanted between individuals of different species. Since, the tissues of donor and recipient are extremely different, they trigger a rapid and intense rejection of graft, which is very difficult to suppress. Transplanting a baboon’s heart into a human is an example of xenograft.

1. Autograft
2. Isograft
3. Allograft
4. Xenograft

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1M
Inflammatory mediators released from degranulating mast cells in type I hypersensitivity reaction causes allergies. When a sensitized individual’s contact with an allergen, many mast cells may degranulate simultaneously, releasing increased amounts of histamines and other inflammatory mediators into the bloodstream.
The chemicals released may exceed the body’s ability to adjust, resulting in acute anaphylaxis or anaphylactic shock. Thus, it could be ascertained that acute anaphylaxis could be associated with type I hypersensitivity. Hence, the given immune system complication matches with the option- A. Type I hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1MC

• Immunoglobin A or (IgA) are secretory immunoglobulins found in mucous secretions like saliva, tears, and colostrum. It plays a major role in mucosal immunity. It does not mediate type-I hypersensitivity. Hence, the option (a) is incorrect.
  Immunoglobin M or (IgM) is the first antibody to appear in the primary immune response. It is commonly called natural antibody because it is formed in the blood even before primary immune response. It does not mediate type- I hypersensitivity. Hence, the option (b) is incorrect.
• Immunoglobin G or (IgG) is the only immunoglobulin that crosses the human placenta and thus offers a passive protection to the newborn babies for about 6-9 months. IgG neutralizes toxins and viruses. IgG binds to bacteria, opsonizes them, thereby enhance their phagocytosis and elimination. It provides humoral immunity. It does not mediate type-I hypersensitivity. Hence, option (c) is incorrect.
• Immunoglobin D or (IgD) has not been shown to have antibody activity and it does not mediate any functions attributed to immunoglobulins. IgD binds to basophils and mast cells and activates them to secrete antimicrobial factors to participate in respiratory immune defense. It does not mediate anaphylactic reaction. Hence, the option (d) is incorrect.
• Immunoglobin E or (IgE) -antigen interaction on mast cells results in degranulation of the mast cells and inflammatory mediators are released. Histamines, kinens, proteases, leukotrienes, prostaglandins are the inflammatory mediators that triggers type I hypersensitivity reactions. IgE provides immunity against worms, protozoan parasites. The immunoglobulin class that mediates type I hypersensitivity is (e) IgE.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1MTF
The given statement, “Cyclosporine is released by degranulating mast cells” is False.
Cyclosporine is an immunosuppressive drug, which involves treatment with antibodies against T cells or their receptors. Degranulating mast cells release histamines, kinins, proteases, leukotrienes, prostaglandins, and other inflammatory mast cells.
Hence, the correct statement is “Histamines, proteases, and kinins are released by degranulating mast cells.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 1SA
Acquired immunodeficiency syndrome was discovered in 1981, which emerged as a worldwide pandemic disease. AIDS is a syndrome; it is not a single disease. Syndrome is defined as a group of signs, symptoms, and diseases associated with a common pathology.
Several opportunistic (or) rare infections associated with a severe decrease in the number of CD4⁺ cells and a positive test showing the presence of HIV. The AIDS infection includes skin disease due to shingles and herpes. Disease of nervous system due to meningitis, toxoplasmosis, and cytomegalovirus, respiratory disease caused by tuberculosis, pneumocystis, histoplasmosis and coccidioidomycosis and disease of digestive systems such as chronic diarrhea, thrust, and oral hairy leukoplakia.
Kaposi’s sarcoma is a rare cancer of blood vessels in AIDS patients. AIDS results in dementia in final stages.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 2CT
Physician cannot use skin test to diagnose bacterial disease, similar to tuberculin reaction:
Explanation
A tuberculin response is mediated by memory T cells. It is a delayed type hypersensitivity reaction in which the skin of an individual is exposed to tuberculosis. Moreover, reacts to subcutaneous injection of a protein solution obtained from Mycobacterium tuberculosis. The resulting cell-mediated immune response generates memory T cells that persist in the body. However, other bacteria have unique antigens that trigger type IV hypersensitivity reactions. Immune responses to most of the bacterial infections are antibody mediated. Hence, physicians do not use skin tests to diagnose bacterial diseases.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 2M
Allergic contact dermatitis is a good example of type IV hypersensitivity reaction, which is T-cell mediated damage to chemically modified skin cells. The oil of poisonous ivy and related plants when rubbed against the skin, triggers cell-mediated immune response and results in intensely irritating skin rash called allergic contact dermatitis. Thus, it could be ascertained that allergic contact dermatitis could be associated with type IV hypersensitivity.
Hence, the given immune system complication matches with the option D. Type IV hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 2MC

• Histamines are the significant chemical released from mast cell. They are small molecules related to the amino acid histidine. Allergen binds to IgE molecule on sensitized mast cell. This binding triggers the sensitized mast cells to release the inflammatory chemicals. Inflammatory mediators mainly histamines are released from degranulated mast cells in type I hypersensitivity. Hence, the correct option is (c) histamine.
• Immunoglobulins are glycoproteins formed in response to an antigen and react specifically with that antigen. It is not an inflammatory mediator released by degranulating mast cells in type I hypersensitivity. Hence, the option (a) is incorrect.
• Complement is a heat-labile serum protein, in which, component involves in lysis of antigen by forming membrane attack complex. They are not mediators that cause allergic reaction. Hence, the option (b) is incorrect.
• Interleukin are not the inflammatory mediators released by degranulating mast cells. They do not cause type anaphylactic or type I hypersensitivity. Hence, the option (d) is incorrect.
• Prostaglandins are produced when allergens bind to IgE on mast cell, which activates other enzymes that trigger the production of leukotrienes and prostaglandis. They are not the major mediator released by degranulating mast cells in type I hypersensitivity. Hence, the option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 2MTF
The given statement, “Type III hypersensitivity reactions may lead to the development of glomerulonephritis” is True.
In type III hypersensitivity reaction, excessive amounts of immune complexes are deposited in tissues, where they cause significant tissue damage. If large amount of immune complexes form in the blood stream, they may be filtered out by the glomeruli of the kidney, causing glomerulonephritis, which can result in kidney failure.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 2SA
Human population of approximately 85% carries Rh antigen, which is also found in rhesus monkeys. The Rh antigens are the second most common antigen, after ABO blood group. If Rh antigens are present on the surface RBC it is denoted as Rh⁺ve, vice versa.
If a woman is Rh^–ve (negative) blood group carrying an Rh⁺ve (positive) fetus, the new born baby have risk of getting new born hemolytic disease. In which antibodies made by the mother against the Rh antigen may cross the placenta and destroy the fetus’s red blood cells.
“RhoGAM” administered to pregnant Rh-women may prevent this disease. If an Rh-positive blood group woman is carrying an Rh-ve (negative) fetus, the fetus doesn’t have the risk of new born hemolytic disease, in which no antibodies are produced which destroys the fetus’s red blood cells.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 3CT
Clinical consequences of autoimmune response to estrogen receptors:
Explanation
Systemic consequences are resulted when an autoimmune response is bound to estrogen. This is due to the presence of different cells producing estrogen receptors. There is reduction in fertility when any damage occurs to ovaries. Moreover, there is alteration in menstrual cycle in damaging the cells of endometrial. Since, the cells are involved in the growth of bone, which consists of receptors for estrogen there is impairment in remodeling.
Furthermore, the estrogen receptors in hypothalamus are targeted with high diversity and are not protected by blood-brain barrier. However, hypothalamus controls the regulation of endocrine functions. Thus, the estrogen receptors are targeted by an immune response that supports in fighting against estrogen-responsive cancers.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 3M
Systemic lupus erythematosus is an immune complex-mediated hypersensitivity reaction. It is a good example of type III hypersensitivity disease that affects multiple organs. Patients with generalized immunological disorder make antibodies against numerous self-antigens found in normal organs and tissues, giving rise to many different pathological lesions and clinical manifestations.
Development of self-reactive antibodies called autoantibodies bind to many autoantigens, especially the patient’s DNA (deoxyribonucleic acid). Thus, it could be ascertained that systemic lupus erythematosus could be associated with type III hypersensitivity.
Hence, the given immune system complication matches with the option C. Type III hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 3MC

• Rh antigen is present in 85% of human population, which is also found in rhesus monkeys. If an Rh-negative pregnant woman is carrying an Rh-positive fetus, the fetus may be at risk of hemolytic disease of the new born, in which, antibodies made by the mother go against the Rh antigen. This may result in destruction of the fetus’s red blood cells.
  Hence, the correct option (d) rhesus antigen.
• Major Histocompatibility (MHC) protein plays a major role in grafting. If MHC antigens are similar in both donor and recipient, graft rejection will not occur. If MHC antigens are different, graft rejection occurs. MHC proteins are not the blood group antigens, which causes hemolytic disease of newborn. Hence, the option (a) is incorrect.
• MN antigen is not blood group antigens. They do not cause hemolytic disease of the newborn. Hence, option (b) is incorrect.
• The most important of the blood group antigens is the ABO group, which is largely responsible for transfusion reactions. Hemolytic disease of the newborn is caused by antibodies against Rh blood group antigen. Hence, option (c) is incorrect.
  Type II protein is not a blood group antigen. They do not cause hemolytic disease in newborn. Hence, option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 3MTF
The given statement, “ABO blood group antigens are found on nucleated cells” is False.
ABO blood group antigens are present on surface of red blood cells. The most important of the blood group antigens is the ABO group, which is largely responsible for transfusion reactions. ABO blood group antigens are not found in nucleated cells.
Hence, the correct statement is “ABO blood group antigens are found on red blood cells.”

Microbiology with Diseases by Taxonomy Chapter 18 Answers 3SA
In allergic individuals plasma cells produce IgE in response to allergens. High levels of IgE are produced in only some allergic individuals. The main reason is exposure to environmental factors during infancy and childhood to high levels of indoor antigens such as cigarette smoke, dust mites, and molds. Hence, the sensitized individuals become hypersensitive.
Everyone is exposed to antigens in the environment, which triggers an immune response resulting in the production of IgG. But when cytokines from type II helper T lymphocytes activate the B lymphocytes in allergic persons, the B lymphocytes become turned into plasma cells, switches to IgE instead of producing IgG.
Following a sensitized individual’s contact with an allergen, many mast cells may degranulate simultaneously, releasing massive amounts of histamine and other inflammatory mediators into the bloodstream. The release of chemicals may exceed the body’s ability to adjust, resulting in anaphylactic shock.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 4CT
Defects in B-cells produce bacterial infections, while defects in T-cells produce viral disease:
Explanation
Antibody-mediated responses with extracellular bacteria are effective in fighting against bacterial infections. Moreover, some people suffer from bacterial diseases that lack B-cells. Additionally, immune responses of cell mediated fights effectively with pathogens like intracellular viruses. Thus, people who are devoid of T-cells will produce viral infections.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 4M
Allografts are grafts transplanted between genetically distinct members of the same species. Most grafts performed in humans are allografts. Since the MHC (major histocompatibility complex) proteins of the allograft are different from those of recipient. Allografts induce strong type IV hypersensitivity, resulting in graft rejection. Thus, it could be ascertained that allograft rejection could be associated with type IV hypersensitivity.
Hence, the given immune system complication matches with the option D. Type IV hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 4MC

• Farmer’s lung is one form of hypersensitivity pneumonitis, caused when immune complexes are deposited in the lung. It is a type III hypersensitivity reaction, occurs in farmers when they are chronically exposed to mold spores. This makes option (c) a type III hypersensitivity to mold spores.
• A type I hypersensitivity reaction to grass pollen is an allergic reaction. It results from the release of inflammatory molecules such as histamine in response to the pollen grass allergen. Farmer’s lung is a type III hypersensitivity reaction. Hence, the option (a) is incorrect.
• A type II hypersensitivity reaction results when cells are destroyed by an immune response. A significant example of type II hypersensitivity is incompatible blood transfusion and hemolytic disease of the newborn. Farmer’s lung is a type III hypersensitivity reaction. Hence, the option (b) is incorrect.
• A type IV hypersensitivity reaction is also called delayed hypersensitivity or cell-mediated hypersensitivity; it is a T cell-mediated inflammatory reaction. Farmer’s lung is type III hypersensitivity. Hence, the option (d) is incorrect.
• Farmer’s lung is a hypersensitivity pneumonitis resulting from a type III hypersensitivity to mold spores. Immune complexes are deposited in lung, where they cause significant tissue damage. Hence, the option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 4MTF
The given statement, “the tuberculin reaction is a type I hypersensitivity” is False.
The tuberculin reaction is a good example of type IV or delayed type hypersensitive reaction, in which T cell-mediated inflammatory reaction takes 24-72 hours to occur. Protein extract of Mycobacterium tuberculosis is injected into the skin of an individual who has been infected with Mycobacterium tuberculosis.
A positive tuberculin test shows hard, red swelling of 10 nm in diameter. Tuberculin reaction is not an allergic reaction or type I anaphylactic hypersensitivity reaction.
Hence, the correct statement is “the tuberculin reaction is a type IV hypersensitivity.”

Microbiology with Diseases by Taxonomy Chapter 18 Answers 4SA
Graft types are named according to the relation between donor and the recipient. A graft is called an autograft when tissues are moved to a different location within the same individual. Foreign antigens are not expressed in autograft; hence they do not trigger immune response. A best example for autograft includes, grafting of skin from one area of the body to another to cover a burn area, (or) use of a leg vein to bypass blocked coronary arteries.
Isografts are grafts transplanted between genetically identical individuals like siblings or clones. The MHC proteins are identical in these individuals; hence the immune system of the recipient cannot differentiate, between the grafted cells and its own normal body cells. Thus Isografts are not rejected since they do not trigger immune response.
Allografts are grafts transplanted between genetically distinct members of the same species. In humans, most of the grafting performed is allograft. Since, the MHC proteins are not same in donor and recipient, it triggers strong type IV hypersensitivity reaction which results in graft rejection. Rejection of graft is suppressed, with immunosuppressive drugs.
Xenografts are grafts transplanted between individuals of different species. Since, the tissues of donor and recipient are extremely different, they trigger a rapid and intense rejection of graft, which is very difficult to suppress. Xenografts from matured animals are not commonly used in therapy. Transplanting a baboon’s heart into a human is an example of xenograft.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 5CT
The illness cause death in patients will combined immunodeficiency:
Explanation
AIDS is a syndrome with several opportunistic or rare infections, associated with several decrease in the number of CD4 cells.

1. AIDS (acquired immunodeficiency syndrome) causes skin infections like shingles and herpes.
2. Moreover, diseases of nervous system include meningitis, toxoplasmosis, and disease of the respiratory system, includes tuberculosis, pneumonia, histoplasmosis, and coccidioidomycosis.
3. Furthermore, disease of digestive system includes diarrhea, thrush, and oral hairy leukoplankia, besides final stages results in dementia.
4. In AIDS patients, a rare cancer is found in blood vessels called Kaposi’s sarcoma. Hence, persons with AIDS or combined immunodeficiency die due to opportunistic infections.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 5M
Acquired immunodeficiency syndrome (AIDS) is defined as the presence of several opportunistic infections or rare infections associated with a severe decrease in the number of CD4 cells and a positive test showing the presence of human immunodeficiency virus (HIV). This could be ascertained that AIDS is not a hypersensitivity reaction. Hence, the given immune system complication matches with the option E. Not a hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 5MC
The tuberculin when injected into tuberculosis infected person, a red, hard swelling of about 10 mm or greater in diameter indicates positive tuberculin test. Inflammation reaches greater intensity within 24-72 hours and may persist for several weeks.

• A patient infected with Mycobacterium tuberculosis when exposed to tuberculosis antigens shows positive tuberculin result. A positive tuberculin skin test indicates that a patient not immunized against tuberculosis (c) has been exposed to tuberculosis antigens.
• A patient infected with tuberculosis, when exposed to a protein extract of the Mycobacterium tuberculosis, a red, hard swelling of 10 mm or greater in diameter indicates positive tuberculin test. Hence, option (a) is incorrect.
• A positive tuberculin skin test indicates that a patient not immunized against tuberculosis, when injected with a protein extract of Mycobacterium tuberculosis shows a hard swelling of 10 mm or greater in diameter. It indicates that the patient is having tuberculosis infection. Hence, option (b) is incorrect.
• A positive tuberculin test indicates that the patient is infected with tuberculosis; it is not that they are susceptible to tuberculosis. They already have the infection. Hence, option (d) is incorrect.
• If the patient is infected with tuberculosis, a red hard swelling occurs in patient when injected with protein extract of Mycobacterium tuberculosis indicating positive tuberculin test. They are not resistant to tuberculosis. Hence, option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 5MTF
The given statement, “Graft-versus-host disease can follow a bone marrow isograft” is False.
Surgical organ or tissue grafting can be made between genetically dissimilar individuals called as allograft. If it is not treated with immunosuppressive drugs, an organ donor’s cells attack the recipient’s body. Isograft is an organ or tissue graft made between genetically identical individuals.
Hence, the correct statement is “Graft-versus-host disease can follow a bone marrow allograft.”

Microbiology with Diseases by Taxonomy Chapter 18 Answers 5SA
Person producing large amount of IgE experience anaphylactic shock, instead of IgG:
Explanation
Immunosuppressive drugs play a major role in the success of modern transplantation. The four classes of immunosuppressive drugs include glucocorticoids, cytotoxic drugs, cyclosporine, and lymphocyte-depleting therapies.

1. Glucocorticoids are corticosteroids, used as immunosuppressive agents for many years. Prednisone and methyl prednisolone are examples of glucocorticoids. The drugs suppress the response of T cells to antigen and inhibit T cell cytotoxicity and mechanism of cytokine production.
2. Cytotoxic drugs inhibit cell division nonspecifically. Cyclophosphamide, azathioprine, mycophenolate mofetil, brequinar sodium, and leflunomide are examples of cytotoxic drugs. Cyclophosphamides cross-link daughter DNA molecules in mitotic cells, preventing their separation and blocking mitosis. It impairs both B cell and T cell responses.
3. Azathioprine is a purine analog, which competes with purines during the synthesis of nucleic acids. Thus, blocks DNA replication and suppressing both primary and secondary antibody responses. Mycophenolate mofetil is a cytotoxic drug, which inhibits purine synthesis. Brequinar sodium and leflunomide inhibits pyrimidine synthesis to inhibit cellular replication.
4. Cyclosporine drug is a polypeptide derived from fungi, preventing interleukins and interferon produced by T cells, thereby blocking Th1 responses. Cyclosporine acts on activated T cells. It is less toxic than the other nonspecific drugs. When the drug is given to prevent allograft rejection, only activated T cells attack the graft are suppressed.
5. Lymphocyte-depleting therapies are used to reduce the adverse side effects of less specific immunosuppressive drugs. One of the techniques includes administering an antiserum called antilympocyte globulin, which is specific for lymphocytes. The modes of action of the therapies are, kills T cells nonspecifically, kills activated T cells, and IL-2 receptors are inhibited.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 6CT
Illnesses that cause death in patients when combines with AIDS:
Explanation
Tissues are different in pigs and humans where matching of tissue is not possible in xenografts. This is because different MHC (major histocompatibility) genes and proteins exist in pigs. Moreover, the xenografts have antigens that will be recognized as non-self.
In addition, Xenografts provoke rapid and intense rejection that is difficult to suppress. Therefore, xenografts require immunosuppressive therapy that leaves the recipient, deadly infections. Hence, xenografts from mature animals are not commonly used therapeutically.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 6M
The grafts are called transplants. The various organs like skin, liver, heart are transplanted within an individual (or) in between the un-related individuals.
There are several types of grafts are used in the transplantation:

• Autografts (The grafts are transplanted within the individual)
• Allografts (The grafts are transplanted between the genetically related species)
• Isografts (The grafts are transplanted between the two genetically related individuals, for example twins )
• Xenografts (the grafts transplanted between the different species. Those do not have genetic relatedness )

The main reason behind the graft rejection is the immunological reaction between foreign MHC complexes on the surface of host cells and recipient cells. The class I and II MHC proteins are involved in the graft versus host rejection.
When graft (donated) bone marrow T cells may consider the patient’s cells as foreign, mounting an immunological graft rejection against the recipient. It is a good example of type IV hypersensitivity. Thus it could be ascertained that graft-versus-host disease could be associated with type IV hypersensitivity.
6. Graft-versus-host disease (d) Type IV hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 6MC

• Systemic lupus erythematosus is a systemic autoimmune disease that affects multiple organs. It is also a type III hypersensitivity in which autoantibodies bind to many autoantigens, especially to the patient’s DNA. Hence, the correct option is (e) Systemic lupus erythematosus.
• Autoimmune disease is production of autoantibodies or cytotoxic T cells against normal body components. Heart attack is not an autoimmune disease; it is caused mainly due to blockage in arteries. Hence, the option (a) is incorrect.
• Acute anaphylaxis is caused when massive amounts of histamine are released from degranulating mast cells into the bloodstream. The result of chemicals may exceed the body’s ability to adjust. Autoantibodies ate not produced against normal body components in acute anaphylaxis. Hence, the option (b) is incorrect.
• Farmer’s lung is one form of hypersensitivity pneumonitis, caused when immune complexes are deposited in the lung. It is a type III hypersensitivity reaction. It is different from autoimmune disease. Hence, the option (c) is incorrect.
• Graft-versus-host rejection is transplantation of an organ or tissue from a donor to a recipient, in which, the donor tissues are considered as foreign, an immune response against them is elicited and the graft will be rejected. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 7CT
Blisters of tuberculin reactions resemble blisters of ivy poison:
Explanation
Tuberculin skin test and oil of poisonous ivy comes under type IV or delayed type hypersensitivity reaction. They both trigger cell-mediated immune response. Tuberculin is mediated by the response of memory T cells. Additionally, an individual is infected with Mycobacterium tuberculosis, results in cell-mediated immune response to generate memory T cells. In tuberculin test, red, hard swelling, and inflammation reaches greater intensity within 24-72 hours. When the lesions developed are examined microscopically, it reveals infiltration of lymphocytes and macrophages.
Furthermore, oil of poisonous ivy is a highly reactive hapten that binds to any protein it contacts. It includes the proteins in the skin when anyone rubs the plant. The chemically modified skin protein is regarded as foreign, triggering a cell-mediated immune response, and resulting in an intensely irritating skin rash called allergic contact dermatitis. Thus, Tc cells destroy skin cells that become acellular, and fluid-filled blisters develop.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 7M
Milk allergy is caused due to adverse reaction, because of different biochemical constituents of the milk from any lactating animal. The milk allergy, it is a type I hypersensitivity reaction. The type I hypersensitivity occurs due to the allergens binds on IgE antibodies that coated on the mast cells and eosinophils.
Upon binding of allergens to the IgE antibodies on the mast cells causes the release of the histamines. These histamines are mainly, responsible for the allergic responses of an individual.
It is a potentially life-threatening condition. Thus it could be ascertained that milk allergy could be associated with type I hypersensitivity.
7. Milk allergy (a) Type I hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 7MC

• A graft is called an auto-graft when tissues are moved to a different location within the same individual. It will not trigger immune response because they do not express foreign antigens. Thus, when a piece of vein from a patient’s leg is transplanted to the same patient’s heart, it is said to be as auto-graft. Hence, the correct option is (b) an autograft.
• Graft rejection is transplanting an organ or tissue from a donor to a recipient, in which the donor tissues are considered as foreign, an immune response against them is elicited and the graft will be rejected. By transferring a piece of vein from a patient’s leg to the same patient’s heart, the graft will not be rejected. Hence, option (a) is incorrect.
• Allografts are grafts transplanted between genetically distinct members of the same species. Allografts typically induce type IV hypersensitivity reaction, resulting in graft rejection. Hence, option (c) is incorrect.
• Type IV hypersensitivity reaction is also known as delayed hypersensitivity reaction in which T cell-mediated inflammatory reaction takes 24-72 hours to reach maximal intensity. It induces immune response, whereas autograft do not trigger immune response. Hence, option (d) is incorrect.
• When cardiac operation is done for transplanting a piece of vein from a patient’s leg to the same patient’s heart it is called autograft. This will not trigger any immune response. The term cardiograft is not used in this condition. Hence, option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 8M
Type III hypersensitivity is an immune complex mediated response. It can affect the lungs, causing a form of pneumonia called hypersensitivity pneumonitis. Individuals become sensitized, when minute mold spores are inhaled deep into the lungs, stimulating the production of antibodies.
A best example is farmer’s lung, which occurs in farmers chronically exposed to spores from moldy hay. Thus it could be ascertained that Farmer’s lung could be matched only with type III hypersensitivity.
8. Farmer’s lung- (c) Type III hyper sensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 8MC
Primary immune-deficiencies are associated with defects in adaptive immunity. Some children fail to develop lymphoid stem cells. As a result, they produce neither B cells nor T cells and cannot mount immune responses.

• A deficiency of both B cells and T cells is most likely (d) a primary immunodeficiency.
• A secondary immunodeficiency disease affects older individuals who normally have less effective cell-mediated immunity. This leads to increased incidence of both viral diseases and certain types of cancer. Hence, the option (a) is incorrect.
• A complex immunodeficiency term is not generally used. Immunodeficiency diseases are basically of two types, primary and acquired or secondary immunodeficiency disease. Hence, the option (b) is incorrect.
• An acquired immunodeficiency disease results from viral infections, which mainly affects older individuals who have less cell-mediated immunity. This also leads to cancer. Hence, the option (c) is incorrect.
• An induced immunodeficiency term is not generally used. Basically immunodeficiencies are of two types, primary and acquired or secondary immunodeficiency disease. Hence, the option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 9M
Allergens when inhaled may provoke type I hypersensitivity in the lungs, leading to severe difficulty in breathing known as asthma. The disease is characterized by wheezing, coughing, excessive production of a thick, sticky mucus, and muscle constriction in bronchi. Asthma is life threatening, which causes suffocation. Thus it could be ascertained that asthma could be associated with type I hypersensitivity.
The type I hypersensitivity is mainly due to the exposure to an allergen. The type I reaction occurred mainly due to release of the histamines, by the mast cells. These mast cells coated with the IgE antibodies.
The allergens responsible, for the asthma condition are bind on the IgE antibodies, upon binding sensitization takes place. This sensitization process leads to production of histamines responsible, for the inflammation.
9. Asthma – (a) Type I hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 9MC
Acquired immunodeficiency syndrome (AIDS) is a condition marked by the presence of antibodies against Human Immunodeficiency Virus (HIV) in conjunction with certain opportunistic infections. In AIDS patient there will be severe decrease in the number of CD4 cells. It causes various diseases in skin, nervous system, digestive system, and dementia during final stages.

• Infection with HIV causes (c) acquired immunodeficiency syndrome.
• Immunodeficiency diseases are classified as primary immunodeficiency diseases, which are detectable near birth and develop in infants and young children, result from some genetic of developmental defect. Examples of primary immunodeficiency diseases include chronic granulomatous disease, in which a child’s neutrophils are incapable of killing ingested bacteria. Hence, option (a) is incorrect.
• Hypersensitivity is said to be allergic reaction. Infection with HIV is not due to allergy. It is an immunodeficiency syndrome. AIDS is not a single disease but a syndrome which is associated with several opportunistic infections with a severe decrease in the number of CD4 cells. Hence, option (b) is incorrect.
• Anaphylaxis is a type I hypersensitivity reaction which gives rise to allergies. HIV infection is not an allergic reaction; it is an acquired immunodeficiency syndrome. Hence, option (d) is incorrect.
• Neither T- cells nor B-cells are produced in children and cannot mount immune responses. The resulting defect in the immune system causes severe combined immunodeficiency disease. HIV infection causes opportunistic infection, it is a syndrome. Hence, option (e) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 10M
Allergens when inhaled may provoke a response in the upper respiratory tract commonly known as hay fever. It is a type I hypersensitivity reaction which causes mild and localized disease. Hay fever is a local allergic reaction; the symptoms include severe nausea, throat and eye discomfort ness, loss of water through the eyes. Thus it could be ascertained that hay fever could be associated with type I hypersensitivity.
The type I hypersensitivity is mainly due to the exposure to an allergen. The type I reaction occurred mainly due to release of the histamines, by the mast cells. These mast cells coated with the IgE antibodies.
The allergens responsible, for the asthma condition are bind on the IgE antibodies, upon binding sensitization takes place. This sensitization process leads to production of histamines responsible, for inflammation in the respiratory track.
10. Hay fever – (a) the type I hypersensitivity.

Microbiology with Diseases by Taxonomy Chapter 18 Answers 10MC

• To counteract various hypersensitivities, patients are administered with drugs like antihistamines, bronchodilators, glucocorticoids, and epinephrine. The hypersensitivities specifically counteracts the inflammatory mediators released by degranulating cells in type I hypersensitivity reaction. Hence, the correct option (e) All the above.
• Antihistamines are administered to counteract histamine. Antihistamines are the drugs administered to counteract the inflammatory mediators released by degranulating cells. It is usually administered to asthma patients. Hence, the correct option is (a) antihistamine.
• Bronchodilator counteracts the effect of inflammatory mediators in type I hypersensitivity reactions. Asthma patients are prescribed with inhalant containing glucocorticoids and bronchodilators to counteract the effect of mediators. Hence, the correct option is (b) bronchodilator.
• Glucocorticoids along with bronchodilators are prescribed to counteract the effect of inflammatory mediators in asthma patients. Hence, the correct option is (c) glucocorticoid.
• Epinephrine is the drug of choice prescribed for patients who suffer from severe type I hypersensitivities. The hormone epinephrine neutralizes the lethal effect of anaphylaxis by relaxing smooth muscle tissue in the lungs, contracting smooth muscle of blood vessels, and reducing vascular permeability. Epinephrine can be injected to patients before their allergic reactions become life threatening. Hence, the correct option is (d) Epinephrine.