NCERT NEET Biology English Medium Part-1 | Chapter 26 : Human health and diseases.

NCERT NEET Biology English Medium Part-1 | Chapter 26 : Human health and diseases.

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Question 1. Who among the following disproved the 'good humor' hypothesis of health using a thermometer to demonstrate normal body temperature in persons with black bile?

1. Hippocrates.
2. Indian Ayurveda system.
3. William Harvey.
4. Louis Pasteur.

Answer: c.

Question 2. Which of the following statements best describes the pathophysiological effect of Streptococcus pneumoniae in humans?

1. It infects the intestinal mucosa causing internal bleeding and fever.
2. It infects the alveoli of the lungs, leading to fluid accumulation and severe respiratory problems.
3. It infects the upper respiratory tract but strictly spares the lungs.
4. It attacks the nervous system causing sustained high fever and chills.

Answer: b.

Question 3. Read the following statements regarding Typhoid fever: (I) Mary Mallon was a classic case of a healthy carrier of Typhoid. (II) The sustained high fever in typhoid is usually $39^\circ C$ to $40^\circ C$. (III) Widal test is an antigen-antibody reaction-based test used for its diagnosis. How many of the above statements are correct?

1. None.
2. One.
3. Two.
4. Three.

Answer: d.

Question 4. Identify the incorrect match between the pathogen, the disease it causes, and its main mode of transmission.

1. Rhinovirus - Common cold - Droplet infection.
2. Entamoeba histolytica - Amoebiasis - Bite of female Anopheles mosquito.
3. Salmonella typhi - Typhoid - Contaminated food and water.
4. Plasmodium falciparum - Malignant malaria - Bite of female Anopheles mosquito.

Answer: b.

Question 5. In the life cycle of Plasmodium, where does the fertilization and development of the parasite take place?

1. Human liver cells.
2. Human Red Blood Cells.
3. Intestine of the mosquito.
4. Salivary glands of the mosquito.

Answer: c.

Question 6. The release of which toxic substance is responsible for the characteristic chill and high fever recurring every three to four days in Malaria?

1. Haemotoxin.
2. Haemozoin.
3. Hirudin.
4. Histamine.

Answer: b.

Question 7. Which of the following parasites requires two hosts to complete its life cycle and enters the human body as sporozoites?

1. Ascaris lumbricoides.
2. Wuchereria bancrofti.
3. Plasmodium vivax.
4. Entamoeba histolytica.

Answer: c.

Question 8. A patient presents with symptoms of constipation, abdominal pain, cramps, stools with excess mucous and blood clots. Which vectors are mechanically responsible for transmitting the causative agent of this disease?

1. Female Anopheles mosquitoes.
2. Houseflies.
3. Aedes mosquitoes.
4. Culex mosquitoes.

Answer: b.

Question 9. In the context of Ascariasis, which of the following statements is primarily responsible for the widespread transmission of the disease in unhygienic conditions?

1. The adult worms excrete toxins into the human bloodstream.
2. The eggs of the parasite are excreted along with the faeces of infected persons which contaminate soil, water, and plants.
3. The parasite forms a symbiotic relationship with intestinal flora.
4. The disease is transmitted via aerosolized droplets.

Answer: b.

Question 10. Elephantiasis, caused by Wuchereria, is characterized by chronic inflammation of the organs in which they live for many years. Which lymphatic vessels are usually affected?

1. Lymphatic vessels of the upper limbs.
2. Lymphatic vessels of the lower limbs.
3. Thoracic duct.
4. Cervical lymph nodes.

Answer: b.

Question 11. Fungi belonging to the genera Microsporum, Trichophyton, and Epidermophyton are responsible for ringworms. Which of the following factors specifically help these fungi to grow?

1. Dry and cold weather.
2. Heat and moisture.
3. High UV radiation exposure.
4. Alkaline skin pH.

Answer: b.

Question 12. Gambusia is a fish that is introduced into ponds for controlling which of the following diseases?

1. Ascariasis.
2. Amoebiasis.
3. Malaria and Dengue.
4. Typhoid and Pneumonia.

Answer: c.

Question 13. Which of the following sets of diseases is completely curable if detected early and treated properly, but relies heavily on vector control for large-scale eradication?

1. AIDS and Cancer.
2. Dengue and Chikungunya.
3. Ringworm and Common cold.
4. Rheumatoid arthritis and Asthma.

Answer: b.

Question 14. Innate immunity is a non-specific type of defense. Which of the following correctly pairs the type of innate barrier with its example?

1. Physical barrier - Acid in the stomach.
2. Physiological barrier - Mucus coating of the respiratory tract.
3. Cellular barrier - Polymorphonuclear leukocytes (PMNL-neutrophils).
4. Cytokine barrier - Saliva in the mouth.

Answer: c.

Question 15. Interferons are proteins secreted by virus-infected cells. What is their primary function in the immune system?

1. They phagocytose viral particles directly.
2. They protect non-infected cells from further viral infection.
3. They act as antibodies against specific viral antigens.
4. They stimulate the liver to produce acute-phase proteins.

Answer: b.

Question 16. The primary response elicited upon the first encounter with a pathogen is of low intensity. The subsequent secondary response is highly intensified. What is the biological basis for this heightened secondary response?

1. Increased production of interferons.
2. Depletion of T-killer cells.
3. Presence of immunological memory cells.
4. Activation of the complement system.

Answer: c.

Question 17. An antibody molecule is represented as $H_2L_2$. Which of the following accurately describes the bonds holding these chains together?

1. Hydrogen bonds.
2. Disulfide bonds.
3. Peptide bonds.
4. Phosphodiester bonds.

Answer: b.

Question 18. Which type of antibody is predominantly found in the colostrum secreted by a mother during the initial days of lactation?

1. IgA.
2. IgG.
3. IgM.
4. IgE.

Answer: a.

Question 19. The cell-mediated immune (CMI) response is primarily responsible for which of the following clinical scenarios?

1. Neutralizing free-floating toxins in the blood.
2. Eliciting an allergic reaction to pollen.
3. Rejection of a transplanted organ such as a kidney.
4. Providing passive immunity to a fetus.

Answer: c.

Question 20. When preformed antibodies against a pathogen are injected directly into a patient, it is called:

1. Natural active immunity.
2. Artificial active immunity.
3. Artificial passive immunity.
4. Natural passive immunity.

Answer: c.

Question 21. Which technology has allowed the production of large quantities of antigenic polypeptides of pathogens in bacteria or yeast for vaccine production?

1. Polymerase Chain Reaction.
2. Recombinant DNA technology.
3. Monoclonal antibody technology.
4. RNA interference.

Answer: b.

Question 22. The hepatitis B vaccine is produced using which of the following organisms?

1. Escherichia coli.
2. Saccharomyces cerevisiae (Yeast).
3. Bacillus thuringiensis.
4. Agrobacterium tumefaciens.

Answer: b.

Question 23. Allergies are caused by the release of chemicals like histamine and serotonin from which type of cells?

1. Macrophages.
2. Neutrophils.
3. Mast cells.
4. T-lymphocytes.

Answer: c.

Question 24. Which of the following drugs can quickly reduce the symptoms of an allergy?

1. Antibiotics and antivirals.
2. Antihistamine, adrenalin, and steroids.
3. Immunosuppressants and chemotherapy.
4. Analgesics and antipyretics.

Answer: b.

Question 25. Rheumatoid arthritis is a disease characterized by the body attacking its own cells. This condition is categorized under:

1. Immunodeficiency diseases.
2. Auto-immune diseases.
3. Infectious diseases.
4. Allergic reactions.

Answer: b.

Question 26. Which of the following organs is a primary lymphoid organ where immature lymphocytes differentiate into antigen-sensitive lymphocytes?

1. Spleen.
2. Lymph nodes.
3. Thymus.
4. Tonsils.

Answer: c.

Question 27. The spleen acts primarily as a filter for the blood. It contains large numbers of which of the following cell types?

1. Mast cells and basophils.
2. Lymphocytes and phagocytes.
3. Erythrocytes and platelets only.
4. Eosinophils and natural killer cells.

Answer: b.

Question 28. Mucosa-Associated Lymphoid Tissue (MALT) constitutes about what percentage of the total lymphoid tissue in the human body?

1. 10 percent.
2. 25 percent.
3. 50 percent.
4. 75 percent.

Answer: c.

Question 29. HIV is a retrovirus, meaning its genetic material consists of:

1. Single-stranded DNA.
2. Double-stranded RNA.
3. Single-stranded RNA.
4. Double-stranded DNA.

Answer: c.

Question 30. During an HIV infection, the virus uses the enzyme reverse transcriptase to perform which critical function?

1. Convert viral DNA into viral RNA.
2. Integrate viral RNA into the host genome directly.
3. Synthesize viral DNA from the viral RNA genome.
4. Cleave host DNA to induce apoptosis.

Answer: c.

Question 31. Which specific type of immune cell acts as an "HIV factory," continually producing new viral particles while the host is infected?

1. B-lymphocytes.
2. Macrophages.
3. Neutrophils.
4. Erythrocytes.

Answer: b.

Question 32. A prominent reason for the severe immunodeficiency in AIDS patients is the progressive decline in the number of:

1. Cytotoxic T-cells.
2. Helper T-lymphocytes ($T_H$).
3. B-memory cells.
4. Natural Killer (NK) cells.

Answer: b.

Question 33. Which diagnostic test is widely used as a primary screening tool for AIDS?

1. Widal test.
2. Polymerase Chain Reaction (PCR).
3. Enzyme Linked Immuno-Sorbent Assay (ELISA).
4. MRI scan.

Answer: c.

Question 34. Normal cells exhibit a property that prevents their uncontrolled growth when they come in contact with other cells. What is this property called?

1. Apoptosis.
2. Contact inhibition.
3. Metastasis.
4. Cellular differentiation.

Answer: b.

Question 35. Tumors that remain confined to their original location and do not spread to other parts of the body are known as:

1. Malignant tumors.
2. Metastatic tumors.
3. Benign tumors.
4. Secondary tumors.

Answer: c.

Question 36. The most feared property of malignant tumors, where cells slough off and travel through the blood to form new tumors elsewhere, is called:

1. Contact inhibition.
2. Metastasis.
3. Neoplastic transformation.
4. Angiogenesis.

Answer: b.

Question 37. Physical, chemical, or biological agents that induce the transformation of normal cells into cancerous cells are broadly called:

1. Teratogens.
2. Mutagens.
3. Carcinogens.
4. Pathogens.

Answer: c.

Question 38. Cellular oncogenes (c-onc) or proto-oncogenes are present in normal cells. Under what conditions do they contribute to cancer?

1. When they are completely deleted from the genome.
2. When they are inactivated by tumor suppressor genes.
3. When they are activated under certain conditions leading to oncogenic transformation.
4. When they are transcribed into reverse transcriptase.

Answer: c.

Question 39. In suspected cases of cancer, a piece of the tissue is cut and examined under a microscope by a pathologist. This technique is known as:

1. Radiography.
2. Biopsy and histopathology.
3. Computed Tomography.
4. Magnetic Resonance Imaging.

Answer: b.

Question 40. Magnetic Resonance Imaging (MRI) is a superior diagnostic tool for detecting pathological and physiological changes in living tissue because it utilizes:

1. Strong magnetic fields and non-ionising radiations.
2. X-rays and computer processing.
3. Gamma rays and radioactive tracers.
4. High-frequency sound waves.

Answer: a.

Question 41. Biological response modifiers such as $\alpha$-interferon are used in cancer treatment primarily to:

1. Directly kill the rapidly dividing cancer cells.
2. Activate the immune system to help destroy the tumor.
3. Block the blood supply to the tumor tissue.
4. Prevent the side effects of chemotherapy like hair loss.

Answer: b.

Question 42. Opioids are drugs that bind to specific opioid receptors present predominantly in the:

1. Lungs and kidneys.
2. Central nervous system and gastrointestinal tract.
3. Liver and spleen.
4. Heart and blood vessels.

Answer: b.

Question 43. Heroin, commonly called smack, is chemically identified as:

1. Diacetylmorphine.
2. Delta-9-tetrahydrocannabinol.
3. Methylenedioxymethamphetamine.
4. Lysergic acid diethylamide.

Answer: a.

Question 44. Morphine is extracted from the latex of which plant?

1. Cannabis sativa.
2. Papaver somniferum.
3. Erythroxylum coca.
4. Atropa belladonna.

Answer: b.

Question 45. Cannabinoids are known primarily for their effects on which system of the human body?

1. Respiratory system.
2. Cardiovascular system.
3. Excretory system.
4. Endocrine system.

Answer: b.

Question 46. Cocaine, an alkaloid extracted from the coca plant, interferes with the transport of which neurotransmitter?

1. Serotonin.
2. Acetylcholine.
3. Dopamine.
4. GABA.

Answer: c.

Question 47. Which of the following plants possess hallucinogenic properties and are sometimes abused for these effects?

1. Papaver somniferum and Rauwolfia.
2. Atropa belladonna and Datura.
3. Cannabis sativa and Nicotiana tabacum.
4. Erythroxylum coca and Cinchona.

Answer: b.

Question 48. Nicotine, an alkaloid found in tobacco, stimulates the adrenal gland to release adrenaline and nor-adrenaline. What is the immediate physiological effect?

1. Decrease in blood pressure and heart rate.
2. Increase in blood pressure and heart rate.
3. Deep relaxation and sleep induction.
4. Reduction in blood sugar levels.

Answer: b.

Question 49. Smoking increases the concentration of which toxic gas in the blood, leading to a deficiency of oxygen bound to hemoglobin?

1. Carbon dioxide.
2. Carbon monoxide.
3. Nitrogen dioxide.
4. Sulfur dioxide.

Answer: b.

Question 50. The period of adolescence, usually linking childhood and adulthood, falls between what ages?

1. 5-10 years.
2. 12-18 years.
3. 18-25 years.
4. 25-30 years.

Answer: b.

Question 51. The state of psychological attachment to certain effects such as euphoria and a temporary feeling of well-being associated with drugs and alcohol is termed:

1. Addiction.
2. Dependence.
3. Tolerance.
4. Withdrawal.

Answer: a.

Question 52. What physiological phenomenon occurs when drug receptors adapt to repeated administration, leading the user to require higher doses to achieve the same effect?

1. Addiction.
2. Withdrawal syndrome.
3. Tolerance.
4. Contact inhibition.

Answer: c.

Question 53. If a regular dose of drugs or alcohol is abruptly discontinued, the body exhibits severe physical symptoms like anxiety, shakiness, nausea, and sweating. This is called:

1. Psychological dependence.
2. Withdrawal syndrome.
3. Drug tolerance.
4. Delirium tremens.

Answer: b.

Question 54. Intravenous drug abusers are at a significantly higher risk of acquiring which of the following serious infections?

1. Typhoid and Cholera.
2. Malaria and Filaria.
3. AIDS and Hepatitis B.
4. Pneumonia and Tuberculosis.

Answer: c.

Question 55. Chronic use of alcohol predominantly damages which vital organ, often leading to a condition known as cirrhosis?

1. Heart.
2. Kidney.
3. Liver.
4. Lungs.

Answer: c.

Question 56. The use of anabolic steroids by female athletes to enhance performance may lead to which of the following side effects?

1. Enlargement of breast tissue.
2. Masculinisation (features like increased facial hair and deepening of voice).
3. Decreased aggression.
4. Premature closing of the growth centers of long bones.

Answer: b.

Question 57. Which of the following diseases is considered an infectious disease?

1. Cancer.
2. Scurvy.
3. Rheumatoid arthritis.
4. Diphtheria.

Answer: d.

Question 58. Assertion (A): The rhinovirus affects the nose and respiratory passage but not the lungs. Reason (R): Common cold usually lasts for 3-7 days and is characterized by nasal congestion and discharge. Choose the correct option.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer: b.

Question 59. Which infectious disease is caused by a protozoan and is common in the human large intestine?

1. Ascariasis.
2. Amoebiasis.
3. Typhoid.
4. Elephantiasis.

Answer: b.

Question 60. The appearance of dry, scaly lesions on various parts of the body such as skin, nails, and scalp accompanied by intense itching is a primary symptom of:

1. Filariasis.
2. Ringworms.
3. Ascariasis.
4. Amoebiasis.

Answer: b.

Question 61. Aedes mosquitoes are known vectors for which pair of diseases?

1. Malaria and Typhoid.
2. Dengue and Chikungunya.
3. Filaria and Amoebiasis.
4. Pneumonia and Common cold.

Answer: b.

Question 62. Which physiological barrier is correctly matched with its protective action?

1. Saliva in mouth - Traps microbes entering the respiratory tract.
2. Tears from eyes - Contain lysozyme to destroy bacterial cell walls.
3. Gastric juice - Provides an alkaline environment to inhibit bacterial growth.
4. Mucus coating - Secretes interferons to fight viral infections.

Answer: b.

Question 63. Polio drops given to children are an example of:

1. Natural active immunity.
2. Artificial active immunity.
3. Artificial passive immunity.
4. Natural passive immunity.

Answer: b.

Question 64. Tetanus immunization involves the administration of:

1. Preformed antibodies or antitoxin.
2. Live attenuated bacteria.
3. Killed whole bacteria.
4. Recombinant proteins.

Answer: a.

Question 65. The exaggerated response of the immune system to certain antigens present in the environment is called allergy. What class of antibodies is produced in this response?

1. IgA.
2. IgG.
3. IgE.
4. IgM.

Answer: c.

Question 66. In the structure of an antibody molecule, the variable regions responsible for binding to specific antigens are located at:

1. The C-terminal ends of the heavy chains only.
2. The N-terminal ends of both heavy and light chains.
3. The hinge region between the heavy chains.
4. The disulfide bridges connecting the chains.

Answer: b.

Question 67. Which of the following is NOT an example of a secondary lymphoid organ?

1. Spleen.
2. Thymus.
3. Tonsils.
4. Peyer's patches of small intestine.

Answer: b.

Question 68. The thymus is quite large at the time of birth but undergoes what change over time?

1. It continues to grow proportionally with age.
2. It converts into a secondary lymphoid organ during puberty.
3. It keeps reducing in size with age and becomes very small by puberty.
4. It migrates to the abdominal cavity to support the spleen.

Answer: c.

Question 69. Which transmission route is generally NOT responsible for spreading HIV?

1. Transfusion of contaminated blood.
2. Sharing of infected needles.
3. Physical contact like shaking hands or hugging.
4. From an infected mother to her child through the placenta.

Answer: c.

Question 70. During the asymptomatic phase of an HIV infection, the virus continues to multiply. The duration between infection and appearance of severe AIDS symptoms can typically be:

1. 1 to 2 weeks.
2. 1 to 2 months.
3. 6 months to 1 year.
4. 5 to 10 years.

Answer: d.

Question 71. In addition to general weakness, AIDS patients become uniquely susceptible to infections that a healthy immune system could easily defeat. A classic example mentioned in NCERT is:

1. Mycobacterium, Toxoplasma, and certain viruses/fungi.
2. Plasmodium falciparum.
3. Salmonella typhi.
4. Wuchereria bancrofti.

Answer: a.

Question 72. Treatment of AIDS with anti-retroviral drugs is only partially effective. They can achieve which of the following?

1. They can completely cure the infection if started early.
2. They can only prolong the life of the patient but cannot prevent death.
3. They reverse the mutation of viral RNA back to DNA permanently.
4. They act as a vaccine to prevent the virus from mutating.

Answer: b.

Question 73. Which organization in India works alongside non-governmental organizations to educate people about AIDS prevention?

1. WHO.
2. NACO (National AIDS Control Organisation).
3. ICMR.
4. CSIR.

Answer: b.

Question 74. Which diagnostic imaging technique uses computed mathematics to generate a 3-D image of the internals of an object from X-rays?

1. Radiography.
2. CT (Computed Tomography).
3. MRI.
4. Ultrasound.

Answer: b.

Question 75. Monoclonal antibodies are employed in cancer diagnosis specifically because they are:

1. Cheaper to produce than traditional biopsies.
2. Highly toxic to cancer cells.
3. Directed against cancer-specific antigens.
4. Capable of mutating proto-oncogenes.

Answer: c.

Question 76. Chemotherapeutic drugs used in cancer treatment often have severe side effects. The two most common side effects are:

1. Hair loss and anemia.
2. Weight gain and diabetes.
3. Hypertension and tachycardia.
4. Liver cirrhosis and jaundice.

Answer: a.

Question 77. Most cancers are treated by a combination of modalities. Which combination is the most standard?

1. Surgery, radiotherapy, and clinical observation.
2. Surgery, radiotherapy, and chemotherapy.
3. Immunotherapy and homoeopathy.
4. Chemotherapy and physiotherapy.

Answer: b.

Question 78. Receptors for cannabinoids are primarily located in the:

1. Kidneys.
2. Heart.
3. Liver.
4. Brain.

Answer: d.

Question 79. Hashish, charas, and ganja are derived from which part(s) of the Cannabis sativa plant?

1. Roots and stem.
2. Flower tops, leaves, and the resin.
3. Seeds exclusively.
4. Bark of the stem.

Answer: b.

Question 80. Crack is a street name for which intensely stimulating central nervous system drug?

1. Heroin.
2. Marijuana.
3. Cocaine.
4. Morphine.

Answer: c.

Question 81. Drugs like barbiturates, amphetamines, and benzodiazepines are clinically used as medicines to treat patients with:

1. Severe infectious diseases.
2. Autoimmune disorders like Rheumatoid arthritis.
3. Mental illnesses like depression and insomnia.
4. Cancer.

Answer: c.

Question 82. Morphine is a highly effective clinical drug specifically useful for:

1. Stimulating the nervous system in comatose patients.
2. Reducing blood pressure in hypertensive emergencies.
3. Acting as a painkiller, especially for patients who have undergone surgery.
4. Curing insomnia in elderly patients.

Answer: c.

Question 83. Tobacco has been used by human beings for more than how many years?

1. 100 years.
2. 200 years.
3. 400 years.
4. 1000 years.

Answer: c.

Question 84. Chewing tobacco is strongly associated with an increased risk of cancer in which specific anatomical area?

1. Lung.
2. Urinary bladder.
3. Oral cavity.
4. Throat.

Answer: c.

Question 85. Assertion (A): Adolescents are vulnerable to drug and alcohol abuse. Reason (R): Curiosity, need for adventure, and experimentation are common motives for youth. Choose the correct option.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Answer: a.

Question 86. Which factor is NOT typically considered an environmental trigger that pushes adolescents toward drug or alcohol use?

1. Peer pressure.
2. Unsupportive family structures.
3. Academic stress.
4. High immune resistance.

Answer: d.

Question 87. The use of alcohol during adolescence may lead to which long-term negative consequence in adulthood?

1. Increased bone density.
2. Heavy drinking habit in adulthood.
3. Immunity against liver cirrhosis.
4. Enhanced synaptic plasticity.

Answer: b.

Question 88. Severe side effects of anabolic steroid abuse in males include:

1. Enlargement of testicles.
2. Decreased sperm production and potential kidney/liver dysfunction.
3. Decreased body hair growth.
4. Deepening of the voice to abnormal levels.

Answer: b.

Question 89. Statement I: The primary lymphoid organs provide micro-environments for the development and maturation of T-lymphocytes. Statement II: The spleen is a primary lymphoid organ. Choose the correct option.

1. Both statements are correct.
2. Both statements are incorrect.
3. Statement I is correct but Statement II is incorrect.
4. Statement I is incorrect but Statement II is correct.

Answer: c.

Question 90. Which immune cells are most heavily involved in identifying and destroying virally infected cells through cell-mediated immunity?

1. B-lymphocytes.
2. T-lymphocytes.
3. Mast cells.
4. Erythrocytes.

Answer: b.

Question 91. A 30-year-old patient reports persistent cough, fever, and blood in sputum. X-ray shows lesions in the lungs. What bacterial disease is most likely?

1. Typhoid.
2. Common Cold.
3. Tuberculosis.
4. Pneumonia.

Answer: d.

Question 92. Identify the disease which is NOT transmitted via a mosquito vector.

1. Malaria.
2. Filariasis.
3. Dengue.
4. Amoebiasis.

Answer: d.

Question 93. Graft rejection is primarily due to the action of:

1. IgE antibodies.
2. Cell-mediated immunity.
3. Humoral immunity.
4. Innate physiological barriers.

Answer: b.

Question 94. The concept of 'vaccination' relies heavily on which fundamental property of the immune system?

1. Autoimmunity.
2. Phagocytosis.
3. Immunological memory.
4. Allergen sensitization.

Answer: c.

Question 95. Anti-venom injection against a snakebite is a classic example of:

1. Artificial active immunity.
2. Artificial passive immunity.
3. Natural active immunity.
4. Innate immunity.

Answer: b.

Question 96. What is the role of an adjuvant when added to a vaccine?

1. It destroys the pathogen entirely before injection.
2. It acts as the primary antigen.
3. It enhances the body's immune response to the antigen.
4. It provides preformed antibodies directly.

Answer: c.

Question 97. The term 'syndrome' in Acquired Immuno Deficiency Syndrome (AIDS) implies:

1. The disease is caused by a single, specific bacteria.
2. The condition involves a group of symptoms pointing to a shared underlying immunodeficiency.
3. The virus mutates too rapidly to be treated.
4. It is a congenital condition.

Answer: b.

Question 98. Which of the following cells act as a physical barrier in the innate immune system?

1. Macrophages in tissue.
2. Epithelial cells of the skin.
3. Natural Killer (NK) cells.
4. Neutrophils in blood.

Answer: b.

Question 99. A person suffering from allergic asthma will typically show elevated levels of which component in their blood?

1. IgA.
2. IgM.
3. IgE.
4. Macrophages.

Answer: c.

Question 100. For an individual attempting to quit a severe alcohol or drug addiction, the safest and most effective approach is:

1. Abruptly stopping all consumption to shock the system.
2. Seeking professional medical help and counseling to manage withdrawal safely.
3. Switching immediately to an alternative illicit drug.
4. Isolating themselves without supervision until cravings stop.

Answer: b.

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