Question
Diseases like dysentery, cholera, typhoid etc., are more common in over crowded human settlements. Why?
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Answer
Overcrowded human settlements are usually unhygienic because of overload on the infrastructure and on hygiene workers. Let us compare two situations to understand this. A person has a bathroom for his exclusive use. He can easily maintain a high level of cleanliness in his bathroom. Another person has to share a bathroom with fifty other people. Maintaining a good hygiene level in such a bathroom would be almost impossible. This will lead to higher risk of getting communicable diseases. Even a simple disease like common cold has more chances of spreading to many people in overcrowded places because the germs would be able to infect more number of people in shorter time span.
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ii. Explain the technique used to separate the cut fragments.
iii. How are the resultant fragments joined to the vector DNA molecule?
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i. How are the desirable DNA sequences cut?
ii. Explain the technique used to separate the cut fragments.
iii. How are the resultant fragments joined to the vector DNA molecule?
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ii. Explain the role of ori and selectable marker in a cloning vector.
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