Human Health and Disease

19 NEET-UG practice questions on Human Health and Disease, part of Zoology. The first 19 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

1. Question 1 · Medium

   A student has sneezing, watery eyes and wheezing each time pollen is in the air. Which combination explains these symptoms?

   1. AIgE, with interferons from virus-infected cells
   2. BIgA, with histamine and serotonin from mast cells
   3. CIgE, with histamine and serotonin from mast cells
   4. DIgG, with adrenaline from the adrenal medulla

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   Answer: C · IgE, with histamine and serotonin from mast cells

   Allergy is an exaggerated response to allergens such as pollen, mediated by IgE antibodies. These lead to the release of histamine and serotonin from mast cells. Anti-histamines, adrenaline and steroids are used to reduce the symptoms.

   • A: Interferons are the antiviral cytokine barrier.
   • B: IgA is the antibody typical of colostrum, not allergy.
   • D: Adrenaline is used to treat allergy rather than causing it.

   Remember this

   Allergy involves IgE and mast cells; adrenaline is a treatment, not the cause of symptoms.

2. Question 2 · Medium

   The alkaloid from Erythroxylum coca produces euphoria and increased energy by interfering with the transport of which neurotransmitter?

   1. AGlycine
   2. BDopamine
   3. CAcetylcholine
   4. DSerotonin

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   Answer: B · Dopamine

   Cocaine, the coca alkaloid, interferes with the transport of dopamine and has a strong stimulating action on the central nervous system. Excess doses can cause hallucinations.

   • A: Glycine is not the neurotransmitter affected by cocaine here.
   • C: Acetylcholine transport is not the cocaine target named in NCERT.
   • D: Serotonin is named in allergy and is not the cocaine target.

   Remember this

   Cocaine is a stimulant acting through dopamine transport; morphine and heroin are depressants acting on opioid receptors.

3. Question 3 · Easy

   Virus-infected cells secrete interferons that protect neighbouring uninfected cells from further infection. These proteins form which innate barrier?

   1. ACellular barrier
   2. BPhysiological barrier
   3. CCytokine barrier
   4. DPhysical barrier

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   Answer: C · Cytokine barrier

   Interferons are cytokines, so this is the cytokine barrier of innate immunity. They protect noninfected cells from further viral infection.

   • A: Cellular barriers are phagocytes and natural killer cells.
   • B: Physiological barriers include gastric acid, saliva and tears.
   • D: Physical barriers are skin and mucus lining.

   Remember this

   Innate barriers: physical (skin, mucus), physiological (acid, saliva, tears), cellular (neutrophils, monocytes, NK cells, macrophages), cytokine (interferons).

4. Question 4 · Easy

   Within a person infected with HIV, which cells are described as an HIV factory because they keep producing the virus?

   1. ANeutrophils
   2. BMacrophages
   3. CB-lymphocytes
   4. DMast cells

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   Answer: B · Macrophages

   HIV enters macrophages, where its RNA is copied into DNA and integrated into the host DNA. Infected macrophages continue to produce virus and so act like an HIV factory.

   • A: Neutrophils are phagocytes but are not the HIV factory.
   • C: B-lymphocytes are not the cells named as the HIV factory.
   • D: Mast cells release histamine in allergy; they are not the HIV factory.

   Remember this

   Macrophages are the HIV factory; helper T-lymphocytes are progressively destroyed, so their number falls.

5. Question 5 · Hard

   Consider these statements on immunity. A. Innate immunity is non-specific and present at the time of birth. B. T-lymphocytes do not secrete antibodies but help B-lymphocytes to produce them. C. The primary response to a pathogen is more intense than the secondary response. D. Antibodies found in the blood and lymph form the cell-mediated response. Choose the correct option.

   1. AA and B only
   2. BA, B and D only
   3. CB and C only
   4. DA, B and C only

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   Answer: A · A and B only

   A and B are correct. C is false because memory makes the second encounter far more intense than the first. D is false because antibodies in body fluids form the humoral response; T-lymphocytes carry out the cell-mediated response.

   • B: This includes D, which confuses humoral with cell-mediated response.
   • C: This leaves out A and includes the false C.
   • D: This includes C, which reverses primary and secondary response strength.

   Remember this

   Specificity, diversity, self versus nonself discrimination and memory characterise acquired immunity; humoral means antibody, cell-mediated means T-cell.

6. Question 6 · Easy

   Heroin, commonly called smack, is obtained from morphine by

   1. AAcetylation
   2. BMethylation
   3. CFermentation
   4. DHydrolysis

   Answer and explanation in LearnFree account

7. Question 7 · Medium

   Match List-I with List-II. List-I (pathogen) A. Trichophyton B. Wuchereria bancrofti C. Haemophilus influenzae D. Rhino virus List-II (feature of the disease) I. Infects the nose and respiratory passage but not the lungs II. Alveoli fill with fluid III. Chronic inflammation of lymphatic vessels of the lower limbs IV. Dry, scaly lesions on skin, nails and scalp

   1. AA-II, B-III, C-IV, D-I
   2. BA-IV, B-III, C-I, D-II
   3. CA-III, B-IV, C-II, D-I
   4. DA-IV, B-III, C-II, D-I

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8. Question 8 · Medium

   A child is born without a functional thymus. Which defect is expected?

   1. ALoss of the main site that filters blood-borne microbes
   2. BPoor maturation of T-lymphocytes, weakening cell-mediated immunity
   3. CLoss of physical barriers such as the skin and mucus lining
   4. DFailure of all blood cell formation, including red blood cells

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9. Question 9 · Easy

   A patient with sustained high fever, stomach pain and constipation has a positive Widal test. The causative organism is

   1. AEntamoeba histolytica
   2. BStreptococcus pneumoniae
   3. CHaemophilus influenzae
   4. DSalmonella typhi

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10. Question 10 · Hard

    Arrange these events of HIV replication in the correct order. A. Viral DNA is incorporated into host cell DNA B. Viral RNA is copied into viral DNA C. The virus enters a macrophage D. Infected cells produce new virus particles

    1. AC, A, B, D
    2. BC, B, A, D
    3. CB, C, A, D
    4. DC, B, D, A

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11. Question 11 · Medium

    Given below are two statements: Statement I: Malignant malaria, caused by Plasmodium falciparum, is the most serious form and can even be fatal. Statement II: Fertilisation and development of Plasmodium gametocytes take place in human red blood cells. Choose the correct answer.

    1. AStatement I is correct but Statement II is incorrect
    2. BStatement I is incorrect but Statement II is correct
    3. CBoth Statement I and Statement II are incorrect
    4. DBoth Statement I and Statement II are correct

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12. Question 12 · Medium

    Read the following on cancer. A. Normal cells show contact inhibition, a property lost by cancer cells. B. Cells of malignant tumours invade and damage surrounding normal tissues. C. Benign tumours characteristically show metastasis. D. Cellular oncogenes occur in normal cells and can cause transformation when activated. Choose the correct option.

    1. AA, B and D only
    2. BA and B only
    3. CB, C and D only
    4. DA, C and D only

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13. Question 13 · Hard

    Match List-I with List-II. List-I (organism) A. Salmonella typhi B. Entamoeba histolytica C. Streptococcus pneumoniae D. Ascaris List-II (site or sign) I. Infects the alveoli of the lungs II. Reaches the small intestine, then other organs through blood III. Infects the large intestine; stools carry mucus and blood clots IV. Blocks the intestinal passage, with internal bleeding and anaemia

    1. AA-I, B-III, C-II, D-IV
    2. BA-II, B-III, C-I, D-IV
    3. CA-II, B-IV, C-I, D-III
    4. DA-III, B-II, C-I, D-IV

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14. Question 14 · Medium

    A farm worker with a deep, soil-contaminated wound is given preformed antitoxin against tetanus at once. The protection he receives is

    1. APassive immunity with a quick response
    2. BActive immunity with a quick response
    3. CActive immunity with lasting memory cells
    4. DPassive immunity with lasting memory cells

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15. Question 15 · Medium

    Match List-I with List-II. List-I (plant) A. Papaver somniferum B. Cannabis sativa C. Atropa belladona D. Tobacco plant List-II (action of its product) I. Stimulates the adrenal gland to release adrenaline and noradrenaline II. Binds opioid receptors in the central nervous system and gut III. Interacts with cannabinoid receptors, mainly in the brain IV. Has hallucinogenic properties

    1. AA-IV, B-III, C-II, D-I
    2. BA-III, B-II, C-IV, D-I
    3. CA-II, B-III, C-IV, D-I
    4. DA-II, B-III, C-I, D-IV

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16. Question 16 · Easy

    Which one of these is NOT a secondary lymphoid organ?

    1. ASpleen
    2. BTonsil
    3. CThymus
    4. DPeyer's patch

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17. Question 17 · Medium

    Assertion A: Patients who receive an organ transplant usually need immunosuppressants for life. Reason R: Graft rejection is caused mainly by antibodies in the blood and lymph. Choose the correct answer.

    1. AA is not correct but R is correct
    2. BBoth A and R are correct and R is the correct explanation of A
    3. CA is correct but R is not correct
    4. DBoth A and R are correct but R is not the correct explanation of A

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18. Question 18 · Medium

    Arrange these events of malaria in a human, starting from the mosquito bite. A. Parasites multiply within liver cells B. Parasites attack red blood cells, rupturing them and releasing haemozoin C. Gametocytes develop in red blood cells D. Sporozoites are injected by a female Anopheles

    1. AD, B, A, C
    2. BD, A, C, B
    3. CA, D, B, C
    4. DD, A, B, C

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19. Question 19 · Hard

    Given below are two statements: Statement I: In HIV infection, viral RNA is first made from viral DNA by reverse transcriptase. Statement II: The number of helper T-lymphocytes rises progressively during the course of the disease. Choose the correct answer.

    1. AStatement I is correct but Statement II is incorrect
    2. BBoth Statement I and Statement II are incorrect
    3. CStatement I is incorrect but Statement II is correct
    4. DBoth Statement I and Statement II are correct

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