Q1. Which are correct for 'Withdrawal Syndrome'? (i) Occurs when drug dose is abruptly discontinued. (ii) Characterised by anxiety, shakiness, and sweating. (iii) It can be relieved when use is resumed.
Correct Answer: (a)
Withdrawal syndrome appears upon abrupt cessation of a drug, includes symptoms like anxiety and sweating, and is relieved by resuming drug use. All statements are true.
Q2. Rheumatoid arthritis is an example of:
Correct Answer: (c)
Rheumatoid arthritis is an autoimmune condition in which the immune system mistakenly attacks the body's own joint tissues, causing chronic inflammation and pain. It is not caused by an external pathogen, nor is it a simple allergic reaction or a Mendelian genetic disorder (though genetics may predispose). Auto‑immunity arises from a failure of self‑tolerance.
Q3. Assertion: Vaccination generates memory B and T-cells.
Reason: Vaccines contain preformed antibodies to neutralize toxins.
Correct Answer: (a)
Vaccines contain antigens (weakened or inactivated pathogens) that stimulate the body to produce memory cells, not preformed antibodies. The reason describes passive immunization (e.g., antiserum), not vaccination. Thus assertion true, reason false.
Q4. The classic case in medicine of a professional cook who was a typhoid carrier is:
Correct Answer: (a)
Mary Mallon, known as 'Typhoid Mary', was an asymptomatic carrier of Salmonella typhi who worked as a cook and transmitted the disease to many people through food. Her case highlighted the importance of identifying carriers and hygiene practices in food handling. The other names are not associated with typhoid carrier status.
Q5. Match the antibody with its role/context:
Antibody
Feature
A. IgA
(I) Secreted from mast cells (Allergy)
B. IgE
(II) Abundant in Colostrum
Correct Answer: (a)
IgA is the main antibody in colostrum (II) and other secretions; IgE is involved in allergic reactions and binds to mast cells (I). The correct match is A–II, B–I.
Q6. Assertion: Normal cells lost the property of contact inhibition in cancer.
Reason: Cancerous cells continue to divide giving rise to masses called tumors.
Correct Answer: (a)
Cancer cells have lost contact inhibition, so they continue to divide even when in contact with neighbours, forming tumours. The reason describes the consequence of that loss (uncontrolled division and mass formation) and directly explains the assertion. Both are true and correctly linked.
Q7. Which of the following is correct? (i) Biology is the youngest of formalised disciplines. (ii) Discovery of antibiotics changed medical practice. (iii) M.S. Swaminathan is known for the Green Revolution.
Correct Answer: (a)
Biology is indeed the youngest formal science; antibiotics revolutionised medicine; and Swaminathan is a key figure in the Green Revolution. All three statements are correct.
Q8. Assertion: Peyer’s patches are secondary lymphoid organs.
Reason: Origin of lymphocytes occurs in Peyer's patches.
Correct Answer: (a)
Peyer's patches are indeed secondary lymphoid organs located in the intestine; they are sites where lymphocytes interact with antigens. However, lymphocyte origin (differentiation) occurs in primary lymphoid organs (bone marrow and thymus), not in Peyer's patches. So assertion true, reason false.
Q9. Assertion: B-lymphocytes produce an army of proteins called antibodies.
Reason: T-cells themselves do not secrete antibodies but help B cells to produce them.
Correct Answer: (b)
Both statements are correct: B cells produce antibodies, and T helper cells assist B cells in antibody production. However, the reason is not an explanation for the assertion; it is a separate fact about T cells. The assertion stands on its own, so the reason is true but does not explain why B cells produce antibodies.
Q10. Match the symptom with the disease:
Disease
Major Symptom
A. Ascariasis
(I) Internal bleeding and muscular pain
B. Amoebiasis
(II) Stools with excess mucous and blood clots
C. Pneumonia
(III) Alveoli filled with fluid
D. Malaria
(IV) Recurring high fever and chill
Correct Answer: (a)
Ascariasis may cause internal bleeding and muscle pain (I); amoebiasis presents with mucous and blood in stools (II); pneumonia fills alveoli with fluid (III); malaria produces recurring fever and chills (IV). These are classic symptom‑disease matches.
Q11. Each antibody molecule has how many peptide chains?
Correct Answer: (c)
An antibody (immunoglobulin) molecule consists of four polypeptide chains: two identical heavy (long) chains and two identical light (short) chains, linked by disulphide bonds, forming a Y‑shaped structure. This H₂L₂ structure is conserved across all antibody classes. Thus, the total number of chains is four.
Q12. Match the abbreviation with its full form:
A. PMNL
(I) Mucosa-associated lymphoid tissue
B. MALT
(II) Enzyme linked immuno-sorbent assay
C. ELISA
(III) Polymorpho-nuclear leukocytes
D. NACO
(IV) National AIDS Control Organisation
Correct Answer: (a)
PMNL = polymorpho‑nuclear leukocytes (III); MALT = mucosa‑associated lymphoid tissue (I); ELISA = enzyme‑linked immunosorbent assay (II); NACO = National AIDS Control Organisation (IV). The pairings are correct.
Q13. The infectious form of Plasmodium that enters the human body through a mosquito bite is:
Correct Answer: (c)
Sporozoites are the infective stage of Plasmodium that are injected into the human bloodstream when an infected female Anopheles mosquito bites. They travel to the liver and multiply, starting the asexual cycle. Trophozoites and gametocytes are stages that appear later in the blood, and haemozoin is a toxic pigment released when red blood cells rupture.
Q14. The diagnostic test used to confirm typhoid fever is:
Correct Answer: (b)
The Widal test detects antibodies against Salmonella typhi antigens in the patient's blood and is the standard serological test for typhoid. ELISA is used for HIV and other infections, while biopsy and MRI are imaging/histological procedures not specific for typhoid diagnosis.
Q15. Allergy is due to the release of chemicals like ______ and ______ from mast cells.
Correct Answer: (b)
Allergic reactions are triggered when mast cells release inflammatory mediators such as histamine and serotonin in response to allergens (e.g., pollen, dust). These chemicals cause vasodilation, increased capillary permeability, and smooth muscle contraction, leading to symptoms like sneezing and itching. Adrenaline, insulin, glucagon, and thyroxine are hormones not typically involved in immediate allergy.
Q16. Assertion: Heroin is a depressant.
Reason: It speeds up body functions.
Correct Answer: (a)
Heroin is a central nervous system depressant; it slows down bodily functions such as breathing and heart rate. The reason states the opposite (speeds up), which is false. Thus assertion true, reason false.
Q17. In pneumonia, the infection occurs specifically in the ______ of the lungs.
Correct Answer: (c)
Pneumonia is an inflammatory condition of the lungs where the alveoli (air sacs) become filled with fluid or pus, making breathing difficult. The infection is typically caused by bacteria or viruses that reach the alveoli via inhalation. The bronchi and trachea are larger airways, and the pleura is the membrane surrounding the lungs.
Q18. Match the following for Human Physiology (Unit 5 intro):
Scientist
Discovery
A. Alfonso Corti
Organ of Corti
Correct Answer: (a)
Alfonso Corti discovered the organ of Corti, a structure in the inner ear essential for hearing. This is a correct historical match.
Q19. The common cold is caused by which group of viruses?
Correct Answer: (b)
Rhinoviruses are the most frequent cause of the common cold, infecting the upper respiratory tract. They are small RNA viruses that multiply in the cooler environment of the nasal passages. Retroviruses (e.g., HIV) and oncogenic viruses are associated with other diseases, and adenoviruses can cause respiratory infections but are less common for the typical cold.
Q20. Match the following for Malaria parasites:
A. Multiplication site 1
Liver cells
B. Multiplication site 2
Red blood cells
C. Storage site in mosquito
Salivary glands
Correct Answer: (a)
In the human host, Plasmodium multiplies first in liver cells, then in red blood cells. In the mosquito, sporozoites are stored in salivary glands for transmission. All matches are correct.
Q21. Match the cancer detection technique with its description:
Column-I (Technique)
Column-II (Description)
A. Biopsy
(I) Uses X-rays to see internal organs
B. Computed Tomography
(II) Staining and examining tissue sections
C. MRI
(III) Uses strong magnetic fields and non-ionising radiation
Correct Answer: (a)
Biopsy involves microscopic examination of stained tissue (II); CT uses X‑rays (I); MRI uses magnetic fields (III). These are accurate descriptions of the respective imaging/diagnostic tools.
Q22. Match the following lymphoid organs:
Column-I (Organ)
Column-II (Type)
A. Bone Marrow
(I) Secondary Lymphoid
B. Thymus
(II) Primary Lymphoid
C. Spleen
(III) Primary Lymphoid
D. Lymph nodes
(IV) Secondary Lymphoid
Correct Answer: (a)
Bone marrow (II) and Thymus (III) are primary lymphoid organs; Spleen (I) and Lymph nodes (IV) are secondary lymphoid organs. The pairing correctly distinguishes primary (where lymphocytes mature) from secondary (where they interact with antigens).
Q23. The toxic substance responsible for the chill and high fever recurring in malaria is:
Correct Answer: (b)
Haemozoin is a haemoglobin breakdown product released when infected red blood cells rupture, causing the cyclical fever and chills characteristic of malaria. Bilirubin is a breakdown product of haemoglobin but does not cause fever. Histamine is involved in allergic reactions, and interferon is an antiviral protein.
Q24. Match the following for allergy treatment:
A. Anti-histamine
Reduction of symptoms
B. Adrenalin
Reduction of symptoms
C. Steroids
Reduction of symptoms
Correct Answer: (a)
Antihistamines, adrenaline, and steroids are all used to reduce allergic symptoms, each by a different mechanism. Thus all are correct.
Q25. Assertion: Acquired immunity is characterized by memory.
Reason: A second encounter with the same pathogen elicits a highly intensified anamnestic response.
Correct Answer: (a)
Memory is the hallmark of acquired immunity: after primary exposure, memory B and T cells persist and respond faster and more robustly upon re‑exposure. The reason describes this anamnestic response and is the direct explanation for why acquired immunity has memory. Thus both are true and correctly linked.
Q26. MALT constitutes about ______ per cent of the lymphoid tissue in the human body.
Correct Answer: (c)
Mucosa‑associated lymphoid tissue (MALT) is found in the respiratory, digestive, and urogenital tracts and makes up about 50% of the body's lymphoid tissue. This high proportion reflects the importance of mucosal surfaces as entry points for pathogens. MALT includes structures like Peyer's patches and tonsils.
Q27. Regarding 'HIV Replication': (i) Viral RNA enters macrophages. (ii) Reverse transcriptase forms viral DNA. (iii) Viral DNA incorporates into the host genome.
Correct Answer: (a)
HIV replication involves viral RNA entering host cells (macrophages, T cells), reverse transcription to DNA, and integration into the host genome. All three steps are correct.
Q28. Match the following for HIV structure:
Component
Nature
A. HIV Genome
RNA
B. Family
Retrovirus
Correct Answer: (a)
HIV has an RNA genome and belongs to the retrovirus family (it uses reverse transcriptase). These are correct features.
Q29. Which of the following phylum/group is being described? (i) These are agents that cause transformation of normal cells into cancerous cells. (ii) Can be physical, chemical or biological. (iii) Examples include UV radiation and tobacco smoke.
Correct Answer: (a)
Carcinogens are cancer‑causing agents, which can be physical (UV), chemical (tobacco smoke), or biological (oncogenic viruses). The description matches carcinogens.
Q30. Correct statements for 'Malaria prevention' include: (i) Use of mosquito nets. (ii) Introducing fishes like Gambusia in ponds. (iii) Spraying insecticides in ditches and swamps.
Correct Answer: (a)
All three measures—mosquito nets, larvivorous fish (like Gambusia), and insecticide spraying—are effective in controlling mosquito vectors and preventing malaria.
Q31. Regarding the AIDS virus (HIV), select the correct statements: (i) It is a member of the retrovirus group. (ii) It has an envelope enclosing the RNA genome. (iii) It is spread by mere touch or shaking hands. (iv) There is a time-lag between infection and symptoms (usually 5-10 years).
Correct Answer: (a)
HIV is a retrovirus with an RNA genome and an envelope; it is not spread by casual contact; and there is a long asymptomatic period (5‑10 years) before AIDS develops. Hence (i), (ii) and (iv) are correct, while (iii) is false.
Q32. Identify the correct statements regarding Typhoid fever: (i) Caused by Salmonella typhi. (ii) Pathogens enter the small intestine through contaminated food. (iii) Sustained high fever (39° to 40°C) is a symptom. (iv) Intestinal perforation may occur in severe cases.
Correct Answer: (a)
All four statements are correct: Salmonella typhi causes typhoid, enters via contaminated food/water, produces sustained high fever, and can lead to intestinal perforation. These are well‑established features of the disease.
Q33. Select correct statements for 'Prevention and Control' of drug abuse: (i) Avoid undue peer pressure. (ii) Education and counselling. (iii) Seeking help from parents and peers. (iv) Looking for danger signs.
Correct Answer: (a)
All four measures—avoiding peer pressure, education/counselling, seeking support, and watching for warning signs—are effective strategies to prevent and control drug abuse. Thus all are correct.
Q34. Match the drug effects:
Drug
Effect
A. Cocaine
(I) Potent stimulating action/Euphoria
B. Heroin
(II) Depressant/Slows body functions
C. Morphine
(III) Sedative/Painkiller
Correct Answer: (a)
Cocaine is a stimulant producing euphoria (I); heroin is a depressant slowing body functions (II); morphine is a sedative and painkiller (III). These effects are correctly paired.
Q35. Which fungi are responsible for ringworm infections?
Correct Answer: (d)
Ringworm is caused by dermatophytes belonging to three genera: Microsporum, Trichophyton, and Epidermophyton. These fungi infect the keratinised tissues of skin, hair, and nails, producing characteristic scaly lesions. All three are responsible, making 'All of these' the correct choice.
Q36. Health is a state of complete ______ well-being.
Correct Answer: (d)
The World Health Organization defines health as a state of complete physical, mental and social well‑being, not merely the absence of disease. This holistic view recognises that emotional and social factors are equally important for overall health. Thus, all three components are required for a person to be truly healthy.
Q37. Assertion: Dependence leads the patient to ignore all social norms.
Reason: The patient needs funds to satiate his/her drug needs.
Correct Answer: (a)
Drug dependence creates a compulsive need to obtain drugs, often pushing individuals to disregard social norms and engage in illegal activities to get money. The reason (need for funds) explains this behavioural change, making it the correct explanation. Both statements are true and linked.
Q38. Assertion: An Rh-ve person should be matched before blood transfusion.
Reason: If exposed to Rh+ve blood, they will form specific antibodies against Rh antigens.
Correct Answer: (a)
Rh‑negative individuals do not naturally have anti‑Rh antibodies, but if they receive Rh‑positive blood, they will produce antibodies against the Rh antigen. Subsequent transfusions with Rh‑positive blood can cause haemolytic reactions. The reason explains why matching is crucial, so both are true and correctly linked.
Q39. Assertion: Many people suffer from allergies in metro cities.
Reason: This is due to the sensitive nature of metro city residents.
Correct Answer: (a)
Allergy prevalence is higher in metropolitan areas due to factors like air pollution, particulate matter, and modern lifestyle, not because residents are inherently 'sensitive'. The reason is false; it is the environment, not personality, that triggers allergies. Thus assertion true, reason false.
Q40. Match the transmission mode with the pathogen:
A. Houseflies
(I) Entamoeba histolytica (Amoebiasis)
B. Female Anopheles
(II) Plasmodium (Malaria)
C. Female Culex (implied)
(III) Wuchereria (Elephantiasis)
Correct Answer: (a)
Houseflies transmit Entamoeba histolytica (amoebiasis) – I; female Anopheles transmits Plasmodium (malaria) – II; female Culex transmits Wuchereria (elephantiasis) – III. These are vector‑pathogen associations.
Q41. Assertion: Tobacco chewing is associated with increased risk of oral cancer.
Reason: Tobacco contains nicotine which stimulates the adrenal gland.
Correct Answer: (a)
Tobacco chewing is a major risk factor for oral cancer due to the presence of carcinogens (nitrosamines). Nicotine does stimulate the adrenal gland, but this is not the cause of cancer; rather, it is the addictive component. Thus both statements are true, but the reason is not the correct explanation for the assertion.
Q42. Which are correct for 'Acquired Immunity'? (i) Pathogen specific. (ii) Characterized by memory. (iii) Uses B and T lymphocytes.
Correct Answer: (a)
Acquired immunity is pathogen‑specific, has memory, and relies on B and T lymphocytes. All three features are correct and define adaptive immunity.
Q43. Match the following for helminths:
Common name
Scientific name
A. Round worm
Ascaris
B. Filarial worm
Wuchereria
Correct Answer: (a) Ascaris is the roundworm; Wuchereria is the filarial worm. Both common names and scientific names are correctly paired.
Q44. Match the following treatment terms:
Term
Treatment Context
A. Immunotherapy
(I) Use of biological response modifiers (interferon)
B. Radiotherapy
(II) Lethal irradiation of tumor cells
C. Surgery
(III) Physical removal of tumor mass
Correct Answer: (a)
Immunotherapy uses biological response modifiers like interferon (I); radiotherapy uses ionising radiation to kill tumour cells (II); surgery physically removes the tumour (III). These are standard cancer treatment modalities.
Q45. Which of the following correctly describes 'Adolescence and Drug Abuse'? (i) Adolescence is a bridge linking childhood and adulthood (12-18 years). (ii) Curiosity and stress are common causes for drug use. (iii) Perception of being 'cool' motivates youngsters to smoke.
Correct Answer: (a)
Adolescence (12‑18 years) is a transitional period; curiosity, stress, and peer pressure (including the desire to appear 'cool') are common reasons for initiating drug use. All statements are correct.
Q46. Elephantiasis or Filariasis is caused by:
Correct Answer: (b)
Filarial worms of the genus Wuchereria (especially W. bancrofti and W. malayi) are the causative agents of elephantiasis. They block lymphatic vessels, leading to severe swelling of limbs and other body parts. Ascaris causes intestinal infection, Microsporum causes ringworm, and Entamoeba causes amoebiasis.
Q47. The property of 'memory' of the immune system is the basis of:
Correct Answer: (b)
Vaccination relies on the immune system's memory: when a vaccine introduces an antigen (weakened or killed pathogen), it triggers the formation of memory B and T cells. Upon subsequent exposure to the same pathogen, these cells mount a rapid and strong response, preventing disease. Allergies are hypersensitive reactions, innate immunity is non‑specific, and contact inhibition is a property of normal cells.
Q48. Interferons are proteins secreted by ______ to protect non-infected cells.
Correct Answer: (b)
Interferons are cytokines produced by virus-infected cells to warn neighbouring cells and stimulate antiviral defenses. They help prevent the spread of viruses to uninfected cells by inducing a state of resistance. Bacterial, cancer, and fungal cells do not typically secrete interferons in this context.
Q49. Match the pathogen with the disease it causes:
Column-I (Pathogen)
Column-II (Disease)
A. Salmonella typhi
(I) Pneumonia
B. Streptococcus pneumoniae
(II) Malaria
C. Plasmodium falciparum
(III) Typhoid
D. Wuchereria bancrofti
(IV) Elephantiasis
Correct Answer: (a) Salmonella typhi causes typhoid (III), Streptococcus pneumoniae causes pneumonia (I), Plasmodium falciparum causes malaria (II), and Wuchereria bancrofti causes elephantiasis (IV). These are standard disease associations.
Q50. Which are correct for 'Primary Lymphoid Organs'? (i) Bone marrow and Thymus. (ii) where immature lymphocytes differentiate. (iii) where lymphocytes migrate after maturation.
Correct Answer: (a)
Primary lymphoid organs (bone marrow, thymus) are sites of lymphocyte differentiation; mature lymphocytes then migrate to secondary lymphoid organs. Thus (i) and (ii) are correct, while (iii) is false.
Q51. Match the following for plant groups:
Scientist
Green Revolution
A. M.S. Swaminathan
Introduction of Mexican wheat
Correct Answer: (a)
M.S. Swaminathan played a key role in the Green Revolution, including the introduction of high‑yielding Mexican wheat varieties to India. The statement is correct.
Q52. Assertion: People who take drugs intravenously are at high risk of AIDS.
Reason: HIV can be transferred by sharing infected needles and syringes.
Correct Answer: (a)
Intravenous drug use often involves sharing needles, which can carry HIV‑infected blood from one user to another. The reason directly explains why this group is at high risk: needle sharing is an efficient transmission route. Both statements are true and correctly linked.
Q53. Assertion: Cannabinoids are known for their effects on the respiratory system.
Reason: They are taken by inhalation and oral ingestion.
Correct Answer: (a)
Cannabinoids are primarily known for their effects on the cardiovascular system (e.g., increased heart rate) and central nervous system, not on the respiratory system. The reason is true because they can be inhaled or ingested, but that does not make the assertion correct. So assertion false, reason true.
Q54. Assertion: Cadaveric grafts for organ transplantation can be taken from anybody.
Reason: The body is able to differentiate 'self' and 'nonself'.
Correct Answer: (a)
The assertion is false because cadaveric organs must be matched for major histocompatibility (HLA) to avoid immune rejection; they cannot be taken from just anyone. The reason is true: the immune system distinguishes self from non‑self, leading to rejection of foreign tissue. So the assertion is false but the reason is true.
Q55. The yellowish fluid colostrum contains which type of antibodies?
Correct Answer: (c)
Colostrum, the first milk produced after birth, is rich in secretory immunoglobulin A (IgA), which provides passive immunity to the newborn by protecting the mucosal surfaces of the gut. IgE is associated with allergies, IgM is the first antibody produced during infection, and IgG is the most abundant in blood.
Q56. Regarding 'Drug Abuse', which statements are true? (i) Opioids bind to specific receptors in the CNS and GI tract. (ii) Cannabinoids are known for their effects on the cardiovascular system. (iii) Cocaine interferes with the transport of dopamine.
Correct Answer: (a)
All three statements are true: opioids act on receptors in the CNS and gut; cannabinoids affect the cardiovascular system (e.g., increase heart rate); cocaine blocks dopamine reuptake. These are established pharmacological effects.
Q57. Identify true statements for 'Innate Immunity' barriers: (i) Tears and saliva contain antimicrobial substances. (ii) Mucus coating traps microbes in respiratory tract. (iii) PMNL stands for polymorpho-nuclear leukocytes.
Correct Answer: (a)
Tears and saliva contain lysozyme; mucus traps pathogens; PMNLs are polymorpho‑nuclear leukocytes. All are true components of innate immunity.
Q58. Malignant malaria, the most serious form of malaria, is caused by:
Correct Answer: (c) Plasmodium falciparum causes malignant tertian malaria, which is the most severe and can be fatal due to cerebral complications and severe anaemia. The other species (P. vivax, P. malariae, P. ovale) typically produce milder, relapsing forms of the disease. P. falciparum has a higher capacity for sequestration in vital organs.
Q59. Which of the following are symptoms of 'Amoebic dysentery'? (i) Constipation and abdominal pain. (ii) Stools with excess mucous. (iii) Blood clots in stools.
Correct Answer: (a)
Amoebiasis (amoebic dysentery) typically presents with abdominal pain, alternating constipation and diarrhoea, and stools containing mucus and blood. Thus all three symptoms are associated with the infection.
Q60. Assertion: Smokers have oxygen deficiency in the body.
Reason: Smoking increases carbon monoxide (CO) content in the blood which reduces the concentration of haembound oxygen.
Correct Answer: (a)
Carbon monoxide in tobacco smoke binds to haemoglobin with much higher affinity than oxygen, forming carboxyhaemoglobin and reducing the blood's oxygen‑carrying capacity. This leads to tissue hypoxia, explaining why smokers may experience oxygen deficiency. Both statements are true and the reason correctly explains the assertion.
Q61. Match the cancer type with the cell source:
Term
Description
A. Carcinogens
Agents causing cancer
B. Oncogenic viruses
Viruses causing cancer
C. Proto-oncogenes
Normal genes that could become oncogenic
Correct Answer: (a)
Carcinogens are cancer‑causing agents; oncogenic viruses are viruses that can cause cancer; proto‑oncogenes are normal genes that can mutate into oncogenes. All definitions are correct.
Q62. Identify the correct principles for STI prevention: (i) Avoid sex with unknown partners. (ii) Always use condoms during coitus. (iii) Seek early detection and treatment.
Correct Answer: (a)
Preventing sexually transmitted infections involves all three: avoiding high‑risk partners, consistent condom use, and early diagnosis/treatment. These are standard public health recommendations.
Q63. Identify correct facts about 'Tobacco': (i) Used for more than 400 years. (ii) Contains nicotine which raises blood pressure. (iii) Smoking is associated with urinary bladder cancer.
Correct Answer: (a)
Tobacco has been used for over 400 years; nicotine increases blood pressure; and smoking is a risk factor for many cancers, including bladder cancer. All statements are true.
Q64. Identify correct features of 'Active Immunity': (i) It is slow and takes time to give a full response. (ii) Antibodies are produced in the host body. (iii) Exposure to antigens is required.
Correct Answer: (a)
Active immunity develops slowly after antigen exposure, involves host‑produced antibodies, and requires prior contact with the antigen. All three features are correct.
Q65. Assertion: HIV/AIDS is not spread by mere touch or physical contact.
Reason: It spreads only through body fluids.
Correct Answer: (a)
HIV is transmitted through exchange of infected blood, semen, vaginal secretions, and breast milk, not by casual contact like hugging or handshaking. The reason correctly explains why touch is not a mode of transmission; body fluid exchange is required. Both statements are true and the reason is the direct explanation.
Q66. Which type of immunity is present at the time of birth and is non-specific?
Correct Answer: (c)
Innate immunity is the body's first line of defence, present from birth, and provides non-specific protection against a wide range of pathogens. It includes physical, physiological, cellular, and cytokine barriers. Acquired immunity develops after exposure and is specific; passive immunity involves receiving antibodies from an external source.
Q67. Which statements about 'Cancer' are correct? (i) Cancer cells lose the property of contact inhibition. (ii) Malignant tumors reach distant sites via blood (metastasis). (iii) Ionising radiations like X-rays can cause DNA damage leading to cancer. (iv) Normal cells lack proto-oncogenes.
Correct Answer: (a)
Statements (i), (ii), and (iii) are correct: cancer cells lose contact inhibition, malignant tumours metastasise, and ionising radiation is a carcinogen. Statement (iv) is false because normal cells do contain proto‑oncogenes, which can become oncogenes when mutated. So the correct set is (i),(ii),(iii).
Q68. Match the cellular barrier with the cell type:
A. Phagocytic WBC
Neutrophils
B. Phagocytic WBC
Monocytes
C. Lymphocyte type
Natural Killer
Correct Answer: (a)
Neutrophils and monocytes are phagocytic white blood cells; natural killer (NK) cells are a type of lymphocyte. All three are correctly classified as cellular components of innate immunity.
Q69. Match the drug with its plant source:
Column-I (Drug)
Column-II (Source)
A. Opioids (Morphine)
(I) Cannabis sativa
B. Cannabinoids
(II) Papaver somniferum
C. Cocaine
(III) Erythroxylum coca
Correct Answer: (a)
Morphine (opioid) comes from Papaver somniferum (opium poppy) – II; cannabinoids from Cannabis sativa – I; cocaine from Erythroxylum coca – III. This is the correct source mapping.
Q70. Match the following for AIDS prevention:
A. NACO
National Level
B. NGO
Non-governmental level
C. WHO
International level
Correct Answer: (a)
NACO (National AIDS Control Organisation) works at the national level, NGOs at non‑governmental levels, and WHO at the international level. All three are correct statements about AIDS prevention efforts.
Q71. Assertion: Benign tumors are not cancerous.
Reason: They remain confined to their original location and do not spread.
Correct Answer: (a)
Benign tumours are non‑cancerous because they are encapsulated, grow slowly, and do not invade other tissues or metastasize. The reason directly describes the defining characteristic of benign tumours, making it the correct explanation. Both are true and correctly linked.
Q72. Assertion: Metastasis is the most feared property of malignant tumors.
Reason: Proliferating cells sloughed from tumors reach distant sites and start new tumors.
Correct Answer: (a)
Metastasis involves the spread of cancer cells through blood or lymph to form secondary tumours at distant locations, making it the most lethal aspect of malignancy. The reason accurately describes this process; cells detach, travel, and colonise new tissues. Thus both are true and the reason correctly explains the assertion.
Q73. Match the Following for antibody chains:
Chain type
Count
A. Heavy chains
2
B. Light chains
2
Correct Answer: (a)
An antibody molecule has two heavy chains and two light chains, so both counts are correct (2 each).
Q74. Which organism causes amoebic dysentery?
Correct Answer: (a) Entamoeba histolytica is a protozoan parasite that infects the large intestine, causing amoebiasis (amoebic dysentery) with symptoms like abdominal pain and bloody stools. Ascaris is a roundworm causing ascariasis, Wuchereria causes filariasis, and Plasmodium causes malaria.
Q75. Regarding 'Immunity', identify the correct statements: (i) B-lymphocytes produce antibodies into the blood. (ii) T-lymphocytes mediate cell-mediated immunity (CMI). (iii) Humoral immune response is antibody-mediated.
Correct Answer: (a)
All three statements are correct: B cells produce antibodies (humoral immunity); T cells are responsible for cell‑mediated immunity; and humoral immunity is indeed antibody‑mediated. These are fundamental aspects of adaptive immunity.
Q76. Assertion: A healthy person can still have a disease.
Reason: Health is only defined as the absence of disease.
Correct Answer: (d)
The assertion is true because health encompasses complete physical, mental and social well‑being, so a person can harbour a disease yet still feel well in other aspects (e.g., an asymptomatic carrier). The reason is false because health is not merely the absence of disease; it is a broader concept. Hence, the assertion holds but the reason does not.
Q77. Heroin is chemically known as:
Correct Answer: (a)
Heroin, a semi‑synthetic opioid, is the diacetyl derivative of morphine and is chemically named diacetylmorphine. It is a potent depressant with high abuse potential. Cannabinoids are derived from cannabis, coca alkaloids from coca leaves, and barbiturates are synthetic CNS depressants unrelated to morphine.
Q78. Which bacterium is responsible for causing typhoid fever in humans?
Correct Answer: (b)
Typhoid fever is caused by the bacterium Salmonella typhi, which enters the body through contaminated food and water. It multiplies in the intestine and can spread to the blood, causing sustained high fever. The other options cause pneumonia, influenza-like illness, and malaria respectively.
Q79. Match the following for secondary metabolites:
Category
Example
A. Alkaloids
(I) Morphine, Codeine
B. Toxins
(II) Abrin, Ricin
C. Drugs
(III) Vinblastin, Curcumin
Correct Answer: (a)
Alkaloids include morphine and codeine (I); toxins include abrin and ricin (II); drugs include vinblastin and curcumin (III). These examples match the categories.
Q80. Match the following for Secondary Metabolites (Table 9.3):
A. Terpenoides
Monoterpenes
B. Lectins
Concanavalin A
C. Polymeric substances
Rubber, Gums
Correct Answer: (a)
Terpenoids include monoterpenes; lectins include concanavalin A; polymeric substances include rubber and gums. These are correct examples from the secondary metabolite classification.
Q81. Assertion: Innate immunity is a non-specific type of defense.
Reason: It consists of various barriers that prevent the entry of foreign agents into the body.
Correct Answer: (a)
Innate immunity provides broad, non‑specific protection through anatomical, physiological, and cellular barriers (e.g., skin, stomach acid, phagocytes). The reason describes these barriers and thus explains why innate immunity is non‑specific: it acts against any invader without requiring prior exposure. Both are true and the reason is correct.
Q82. Regarding 'Ringworm' infection: (i) Dry, scaly lesions on skin/nails/scalp. (ii) Accompanied by intense itching. (iii) Thrives in skin folds like groin or between toes.
Correct Answer: (a)
Ringworm causes dry, scaly, itchy lesions and commonly affects moist areas like skin folds. All three descriptions are correct for this fungal infection.
Q83. AIDS was first reported in the year:
Correct Answer: (c)
Acquired Immunodeficiency Syndrome (AIDS) was first clinically recognised in 1981, when clusters of rare infections (e.g., Pneumocystis pneumonia) and Kaposi's sarcoma were observed in homosexual men. The causative virus, HIV, was identified later in 1983‑84. Earlier years (1951, 1971) predate this recognition.
Q84. Which drug is obtained from the plant Cannabis sativa?
Correct Answer: (c)
The inflorescences of Cannabis sativa contain cannabinoids such as tetrahydrocannabinol (THC), which have psychoactive effects. Cocaine is from coca leaves, morphine from the opium poppy (Papaver somniferum), and nicotine from tobacco (Nicotiana tabacum).
Q85. Assertion: Addiction is a psychological attachment to certain effects like euphoria.
Reason: Repeated use of drugs increases the tolerance level of receptors.
Correct Answer: (a)
Addiction refers to the psychological craving for the pleasurable effects of a drug, while tolerance is a physiological adaptation where higher doses are needed to achieve the same effect. Both are true, but tolerance does not explain the psychological attachment; it explains why dosage increases. So reason is true but not the explanation for addiction.
Q86. Regarding the life cycle of Plasmodium, which statements are true? (i) It requires two hosts: human and mosquitoes. (ii) Parasites multiply initially within the liver cells. (iii) The sexual stages (gametocytes) develop in the mosquito's gut.
Correct Answer: (a)
Statements (i) and (ii) are correct: Plasmodium needs human and mosquito hosts, and multiplies first in liver cells. Statement (iii) is false because gametocytes form in human red blood cells, not in the mosquito gut (fertilisation occurs in the gut). So only (i) and (ii) are true.
Q87. Assertion: Alpha-interferon is given to cancer patients.
Reason: It activates the immune system and helps in destroying the tumor.
Correct Answer: (a)
Alpha‑interferon is a biological response modifier used in cancer therapy to stimulate the immune system (e.g., natural killer cells) against tumour cells. Its immunostimulatory action is the basis for its use, so the reason correctly explains the assertion. Both statements are accurate.
Q88. Assertion: Malarial parasite requires two hosts to complete its life cycle.
Reason: Female Anopheles mosquito is the vector for malaria.
Correct Answer: (a)
The assertion is correct: Plasmodium must alternate between a human and a mosquito host. The reason is also true and explains why the mosquito is essential—it serves as the vector that transfers the parasite between humans. Thus the reason correctly explains the need for two hosts.
Q89. Identify the correct phylum/group being described: (i) They produce an army of proteins in response to pathogens. (ii) They are found in the blood. (iii) The response is called humoral immune response.
Correct Answer: (a)
B lymphocytes produce antibodies (proteins) in the blood, mediating the humoral immune response. This matches the description given.
Q90. Match the type of barrier in innate immunity:
Column-I (Barrier)
Column-II (Example)
A. Physical barrier
(I) Acid in stomach
B. Physiological barrier
(II) Interferons
C. Cellular barrier
(III) Skin
D. Cytokine barrier
(IV) PMNL-neutrophils
Correct Answer: (a)
Physical barrier: skin (III); physiological: acid in stomach (I); cellular: PMNL‑neutrophils (IV); cytokine: interferons (II). These are the correct pairings from the innate immunity components.
Q91. The property by which normal cells inhibit the uncontrolled growth of other cells is called:
Correct Answer: (b)
Contact inhibition is a regulatory mechanism in normal cells that stops cell division when they come into contact with neighbouring cells. This property helps maintain tissue architecture and prevents overcrowding. Cancer cells lose this inhibition, leading to uncontrolled proliferation and tumour formation.
Q92. Assertion: Morphine is useful for patients who have undergone surgery.
Reason: It is a very effective sedative and painkiller.
Correct Answer: (a)
Morphine, an opioid analgesic, is widely used to manage severe post‑surgical pain because it binds to opioid receptors in the brain and spinal cord, producing potent pain relief and sedation. The reason correctly identifies these properties, making it the explanation for its clinical utility in surgery.
Q93. Match the following for common symptoms:
Pathogen
Transmission
A. Common cold
Droplets/Sneeze
B. Pneumonia
Droplets/Aerosols
Correct Answer: (a)
Both the common cold (rhinoviruses) and pneumonia (bacteria/viruses) are transmitted via droplets and aerosols. Both statements are correct.
Q94. Assertion: Acquired immune response is pathogen specific.
Reason: It is present at the time of birth.
Correct Answer: (a)
The assertion is correct: acquired (adaptive) immunity is specific to a particular pathogen. The reason is false because acquired immunity is not present at birth; it develops after exposure to antigens. Innate immunity is what is present at birth. So assertion true, reason false.
Q95. Regarding 'Antibody structure': (i) Represented as H2L2. (ii) Contains antigen-binding sites. (iii) Light and heavy chains are connected by disulphide bonds.
Correct Answer: (a)
Antibodies have a H₂L₂ structure, possess antigen‑binding sites, and have chains linked by disulphide bonds. All statements are correct.
Q96. Which of the following are correctly described as 'Secondary Lymphoid Organs'? (i) Spleen. (ii) Lymph nodes. (iii) Peyer’s patches of small intestine. (iv) Appendix.
Correct Answer: (a)
All listed organs – spleen, lymph nodes, Peyer's patches, and appendix – are secondary lymphoid organs where lymphocytes interact with antigens. They are not sites of lymphocyte origin (which are bone marrow and thymus). Thus all are correct.
Q97. Assertion: AIDS causes the person to become immuno-deficient.
Reason: There is a progressive decrease in the number of helper T-lymphocytes (TH).
Correct Answer: (a)
HIV infects and destroys CD4+ helper T cells, leading to a decline in their number and severe immunodeficiency. This makes the person susceptible to opportunistic infections. The reason directly explains the immunosuppression, so both are true and correctly linked.
Q98. Which of the following is correct regarding 'Health' according to the provided text? (i) Early Greeks like Hippocrates asserted that health was a balance of humors. (ii) Indian Ayurveda system also supported the humor hypothesis. (iii) William Harvey disproved the 'good humor' hypothesis using thermometers.
Correct Answer: (b)
Statements (i) and (ii) are true: both Greek and Ayurveda traditions believed health depended on humor balance. Statement (iii) is false because Harvey's discovery of circulation and the later use of thermometers were separate contributions; Harvey did not use thermometers himself. Therefore only (i) and (ii) are correct.
Q99. Match the addiction syndrome:
A. Dependence
(I) Characteristic and unpleasant withdrawal syndrome
B. Tolerance
(II) Receptors respond only to higher doses
Correct Answer: (a)
Dependence is marked by withdrawal symptoms when drug use stops (I); tolerance means the body needs higher doses to achieve the same effect (II). These are correctly paired.
Q100. The 'good humor' hypothesis of health was disproved by the discovery of blood circulation by:
Correct Answer: (b)
William Harvey's demonstration of blood circulation provided a physiological basis for health, moving away from the ancient idea of imbalance of four humors. Alongside the later use of thermometers to measure fever, this evidence challenged the purely philosophical 'good humor' model. Hippocrates proposed the humor theory, but Harvey's work was experimental and disproved it.