NEET Biology Human Health and Disease MCQs Set 01

Answer: (c) Haemozoin

Explanation:
1. Haemozoin– Malarial parasite digest haemoglobin and release high quantities of free heme, this free heme is toxic to cells and parasite convert it into an insoluble crystalline form called haemozoin.
2. Haemotoxin– Toxic substances in animal's venom, such as snake's venom.
3. Haemoglobin– Iron containing metalloprotein in red blood cells.
4. Sporozoites– Infectious form of malarial parasite.

Answer: (d) Pneumonia

Explanation:
1. Pneumonia: It is characterised by infection of lungs.
2. Due to filling of fluid in alveoli gas exchange cannot occur properly loading to severe problems in respiration.

Answer: (a) Widal test

Explanation:
1. Mantoux test– Tuberculosis Schick test– Diphtheria Dick test– Scarlet fever.

Answer: (c) It is a parasite in small intestine of man

Explanation:
1. Entamoeba histolytica is a parasite of large intestine of man.

Answer: (a) Plasmodium enters the human body as sporozoites through the bite of freshly moulted female Anopheles mosquito

Explanation:
1. Plasmodium enters the human body as sporozoites through the bite of infected female Anopheles mosquito.

Answer: (d) Gambusia

Explanation:
1. Gambusia is a larvivorous fish that feeds on mosquito larvae.

Answer: (d) Small pox

Explanation:
1. It was a deadly disease which is now completely eradicated by using vaccine discovered by Edward Jenner in 1798.

Answer: (d) Red blood cells of man

Explanation:
1. Gametocyte begin to form in RBC of man and completes its further development to form gametes as sexual cycle in mosquito.

Answer: (c) a, c & d only

Explanation:
1. Typhoid, Cholera and Tuberculosis are caused by bacteria.
2. Elephantiasis is caused by helminth.

Answer: (c) Ringworm

Explanation:
1. It is a fungal disease caused by Microsporum, Trichophyton, Epidermophyton.
2. Botulism– (Food poisining)– Clostridium botulinum– bacterial disease.
3. Conjunctivitis– Viral, bacterial or an allergic reaction.
4. Skin Allergy– Caused by different allergens.

Answer: (d) Innate immunity

Explanation:
1. It is non-specific as it act against any type of foreign agent . Acquired Immunity– It is pathogen specific and it initiates when a host encounters pathogen during first attack Humoral Immunity– Type of acquired immunity– B-lymphocyte mediated in which antibodies are produced.
2. Cell mediated immunity– T-lymphocyte mediated.

Answer: (b) Physiological barrier

Explanation:
1. One of the barrier of innate immunity Physical barrier– Skin, muscous coating of epithelium Cellular barrier– WBC– PMNL, monocytes, NK– cells Cytokine barrier– Interferons.

Answer: (a) IgA

Explanation:
1. IgA– Colostrum is a golden liquid substance that a nursing mother expels from her breasts 24-48 hours after delivery.
2. IgG– Only antibody that can cross the placenta and confer immunity to the foetus.
3. IgE– Mediator in allergic response.
4. IgM– Activates first in initial attack of antigen.

Answer: (c) RNA retrovirus

Explanation:
1. HIV forms DNA from RNA using reverse transcriptase.

Answer: (b) Cancer

Explanation:
1. AIDS– Communicable/infectious disease and fatal disease.
2. Cystic fibrosis– It is a genetic disorder.
3. Cholera– Communicable disease but not fatal.

Answer: (c) Carbon monoxide

Explanation:
1. When the smoke is inhaled into lungs, CO is rapidly absorbed into blood stream and it binds to the haemoglobin in the red blood cells 200 times more effectively than oxygen does.

Answer: (d) Heroin

Explanation:
1. Cocaine: obtained from Erythroxylum coca, generally snorted.
2. Causes hallucinations, and has a potent effect on central nervous system, producing a sense of euphoria and increased energy.
3. Hashish: Obtained from Cannabis plant, taken by inhalation and oral ingestion.
4. Effects on cardiovascular system.

Answer: (d) Alteration of perception, thoughts and feelings

Explanation:
1. Alteration of perception, thoughts and feelings are hallucinations.

Answer: (b) Rhinovirus infects the nose, respiratory passage and lungs

Explanation:
1. Rhinovirus infects nose and respiratory passage but not lungs.

Answer: (c) Typhoid

Explanation:
1. In severe cases intestinal perforation and death may occur in typhoid.
2. Pneumonia: fever, chills, cough and headache.
3. Plague: High fever, lump in the groin or the armpit, red patches on skin.
4. Pertussis: Mild fever, nasal congestion, sneezing, nasal discharge.

Answer: (d) Aedes mosquito

Explanation:
1. Culex mosquito– Vector of Wuchereria bancrofti which causes Elephantiasis.
2. Xenopsylla– Vector of Yersinia pestis which causes plague.
3. Anopheles mosquito– Vector of Plasmodium which causes malaria.

Answer: (c) Yersinia pestis

Explanation:
1. Trichinella spiralis: Causes trichinosis.
2. Salmonella typhimurium: Causes gastroenteritis in mammals.. Xenopsylla: Act as a vector in transmitting plague pathogen Yersinia pestis.

Answer: (c) Preformed antibodies

Explanation:
1. Preformed antibodies are injected in such injury as pathogen i.e., Clostridium tetani produces a neurotoxin- tetanospasmin and a quick response is required to stop the action of antigen which is not done by the formation of our own antibodies as it takes time.
2. Weakened germs and dead germs are used in vaccine to develop immunity against them.
3. Wide spectrum antibiotics is used when a person is suffering from many diseases or infections but not for a single disease/infection.

Answer: (a) The anamnestic response against a pathogen is highly intensified

Explanation:
1. B-lymphocytes produce antibodies T-lymphoctes produce cell mediated response.
2. An antibody is represented by H2L2.

Answer: (d) All of these

Explanation:
1. These all are different barriers under innate immunity.
2. Mucus membrane– Physical barrier Interferons– Cytokine barrier Natural Killer cells– Cellular barrier.

Answer: (b) Vaccination

Explanation:
1. Repeated exposure to the same microbes or illness develops natural active immunity.