Short Answer TypeWrite the source and the effect on the human body of the following drugs:
(i) Morphine
(ii) Cocaine
(iii) Marijuana
A heavily bleeding and bruised road accident victim was brought to a nursing home. The doctor immediately gave him an injection to protect him against a deadly disease.
(a) Write what did the doctor inject into the patient's body.
(b) How do you think this injection would protect the patient against the disease?
(c) Name the disease against which this injection was given and the kind of immunity it provides.
Why is secondary immune response more intense than the primary immune response in human?
Community Service department of your school plan a visit to a slum area near the school with an objective to educate the slum dwellers with respect to health and hygiene.
(a)Why is there a need to organize such visits?
(b)Write the steps you will highlight, as a member of this department, in your interaction with them to enable them to lead a healthy life.(a) Name the group of viruses responsible for causing AIDS in humans. Why are these viruses so named?
(b) List any two ways of transmission of HIV infection in humans, other than sexual contact.
(a) Tobacco plants are damaged severely when infested with Meloidegyne incognitia. Name and explain the strategy that is adopted to stop this infestation.
(b) Name the vector used for introducing the nematode specific gene in tobacco plant.(a) RNA interference or RNAi is a method adopted to prevent infestation of roots of tobacco plants by a nematode Meloidogyne incognita. The method involves silencing of a specific mRNA by a complementary RNA and the formation of ds RNA. The ds RNA, cannot be translated and its expression is blocked. These RNAi genes can be incorporated into the tobacco plant through vectors. The source of this complementary RNA could be from an infection by viruses having RNA genomes or mobile genetic elements (transposons) that replicate via an RNA intermediate. Since the dsRNA cannot be transcribed thus the parasite cannot survive and the plant is protected from it.
(b) Agrobacterium vectors are used for introducing nematode specific genes into the tobacco plant. The DNA is introduced in such a way that it produces both sense and anti-sense RNA in the host cells. The two RNA’s being complementary to each other form double stranded (dsRNA) that initiates RNAi and thus, silences the specific mRNA, of the nematode. The consequence was that the parasite could not survive in a transgenic host expressing specific interfering RNA. The transgenic plant therefore got itself protected from the parasite.
Name the calls HIV (Human Immunodeficiency Virus) gains entry into after infecting the human body. Explain the events that occur in these cells.
It is generally observed that the children who had suffered from chicken - pox in their childhood may not contract the same disease in their adulthood. Explain giving reasons the basis of such an immunity in an individual. Name this kind of immunity.
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