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Questions:

Case Study Questions

5 x 4 = 20

Read the following and answer any four questions from (i) to (v) given below:
A group of teenagers was involved in drug abuse. They used syringes and needles to inject drugs. They indulged in this habit when they became adults. Administration of drug through needles became a piece of cake for them. Raj was the most active drug abuser amongst them and used to take drugs in high profile parties. In a span of time he started losing weight and suffered persistent diarrhoea. He developed constant low grade fever and used to catch opportunistic infection. When he consulted a doctor, he got himself tested for HIV in his blood and finally diagnosed with AIDS.
Based on the above information, answer the following questions.
(i) Select the incorrect statement.

(a) AIDS is a disorder of cell mediated immune system of the body.	(b) AIDS is caused by Human Immunodeficiency virus.
(c) AIDS infections were detected in India for the first time in prostitutes ofChennai, Tamil Nadu in 1986.	(d) December 10 is recalled as World AIDS Day.

(ii) How do you think Raj got AIDS infection?

(a) Through transfusion of HIV infected blood	(b) Sexual intercourse with an infected partner
(c) Sharing towel with infected friend	(d) Use of contaminated needles and syringes to inject drugs

(iii) How AIDS can be diagnosed?

(a) ELISA test

(b) Ames test

(c) Pap's test

(d) Widal test

(iv) How can AIDS be prevented?

(a) Blood tests of blood donor before transfusion to check for the presence of AIDS virus.	(b) Use of disposable needles and syringes for injecting medicines and vaccination
(c) Having protected sex by use of condoms	(d) All of these

(v) Select the correct statement for AIDS virus.

(a) It is rhomboid in shape with a diameter of 10-15 cm.	(b) Its genome consists of ds DNA.
(c) It consists ofreverse transcriptase enzyme.	(d) Its envelope-consists oflipid bilayer and three protein coats.

Read the following and answer any four questions from (i) to (v) given below:
Priya was 4 years old when she contracted chicken pox. It took her around 15 days to recover completely. Now Priya is 5 years old so her mother got her vaccinated few days back for DPT (5th dose) as per immunisation program. Recently she was playing with her friend in the park when her friend accidently fell on iron pipe and badly bruised her knee. She was taken to the hospital where doctor gave her ATS injection and painkillers. Based on the above information, answer the following questions.
(i) Select the correct statement.

(a) Priya has developed natural active immunity against chicken pox.	(b) Priya has developed artificial active immunity against DPT.
(c) Priyas friend has developed artificial passive immunity against tetanus.	(d) All of these

(ii) Which of the following do you think is an example of natural passive immunity?

(a) Administration of AGS (anti gas gangrene serum) in a person	(b) Transfer of IgA antibodies from mother to baby through mother's milk
(c) A person recovered from viral infection	(d) A child vaccinated for polio

(iii) Which of the following is true for active immunity?

(a) It provides immediate relief.	(b) It is temporary, not long lasting.
(c) It has no side effects	(d) None of these

(iv) Select the incorrect match.

(a) Passive immunity - IgG antibodies crossing placental barrier to reach fetus	(b) Active immunity - Vaccination against corona virus
(c) Active immunity - Administration of antidiphtheria serum in patient	(d) Passive immunity - Fetus having mother's milk

(v) Assertion: A person recovered from measles develops an active immunity against this infection.
Reason: In active immunity, person's own cells develop antibodies in response to infection.

(a) Both assertion and reason are true and reason is the correct explanation of assertion.	(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.	(d) Both assertion and reason are false.

Read the following and answer any four questions from (i) to (v) given below:
Rajesh, Ravi and Rohit are roommates. They are doing their graduation. Few months back Ravi fell ill. It took him around 3 weeks to recover. Both his friends were absolutely healthy at that time. After sometime Rajesh also fell ill from some other disease. This time Ravi and Rohit both contracted the same illness. Based on the above information, answer the following questions.
(i) Which of the following holds true for Ravi's illness?

(a) Ravi was suffering from a communicable disease that is transmitted through vector.

(b) Ravi was suffering from a communicable disease that is transmitted through faecal oral route.

(c) Ravi was suffering from a non-com'municable disease like anaemia.

(d) Ravi was suffering from a non-communicable disease like Down's syndrome.

(ii) Select the correct statement.

(a) Ravi contracted a disease caused by air borne microbes.	(b) Ravi could have suffered a nutritional disorder.
(c) Ravi suffered a non-contagious disease.	(d) Both (b) and (c)

(iii) Which could be correctly said for Rajesh's illness?

(a) Rajeshs illness was due to a microbial infection	(b) Rajesh's illness could be contagious or non-contagious.
(c) Rajesh's illness could be cured by antibiotics.	(d) All of these

(iv) Which of the following may depicts Ravi's and Rajeshs illness?

Ravi	Rajesh
(a) Sickle cell anaemia	Myocardial infection
(b) Whooping cough	Tetanus
(c) Gastritis	Rhinitis
(d) Hypertension	Thyroid

(v) Assertion: Diabetes mellitus is a non-communicable disease which can be completely cured.
Reason: Diabetes mellitus is caused by deficiency of aldosterone hormone.

(a) Both assertion and reason are true and reason is the correct explanation of assertion.

(b) Both assertion and reason are true but reason is not the correct explanation of assertion.

(c) Assertion is true but reason is false.

(d) Both assertion and reason are false

The skeletal structure of a cannabinoid molecule is given above. Answer the following questions.
(a) What are the modes of its consumption by humans?
(b) Name the four different forms in which cannabinoids are produced.

Study the diagram showing the entry of HIV into the human body and the processes that are followed:

(a) Name the human cell 'A' HIV enters into.
(b) Mention the genetic material 'B' HIV releases into the cell.
(c) Identify enzyme 'C'

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Answers Key:

Case Study Questions

5 x 4 = 20

(i) (d) : Every year, December 1 is designated as World AIDS Day.
(ii) (d)
(iii) (a) : ELISA test, also called EIA for enzyme immunoassay is used to detect HIV antibody. It checks for certain proteins that the body makes in response to HIY.
(iv) (d)
(v) (c) : HIV is spherical with a diameter of 90-120 nm. Its genome consists of single stranded RNA. The envelope consists of a lipid bilayer derived from host cell membrane and projection knob like glycoproteins. It contains two protein coats.

(i) (d) : In active immunity, person's own cells produce antibodies in response to infection or vaccination. A person who has recovered from an infection develops natural active immunity whereas artificial active immunity is the resistance induced by vaccines. When ready-made antibodies are directly injected into a person to protect the body against foreign agents, it is called passive immunity.
(ii) (b)
(iii) (c) : Active immunity provides relief only after long period. It is long lasting.
(iv) (c) : Administration of antidiphtheric serum in a patient provides artificial passive immunity.
(v) (a)

(i) (c) : Ravi must have suffered from a noncommunicable disease which cannot be spread from one person to another. Anaemia is caused by deficiency of iron and. lead to general weakness and associated problems. It can be corrected by proper diet and dietary supplements. Down's syndrome is also a non-communicable disease but it is not cured completely. It is a genetic disorder and is congenital.
(ii) (d) : Non-communicable diseases are noncontagious.
(iii) (d)
(iv) (c)
(v) (d) : Diabetes mellitus is a non communicable disease that has no cure. It is caused by deficiency of insulin hormone.

(a) It is consumed by
(i) inhalation and
(ii) oral ingestion.
(b) Marijuana, Hashish, Ganja, Charas.

(a) Macrophage.
(b) RNA (Ribonucleic acid).
(c) Reverse transcriptase.