CBSE biology
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How many chromosomes do drones of honeybee possess? Name the type of cell division involved in the production of sperms by them.
Drones of honey bees are haploid and possess 16 chromosomes.
Drones produce sperms by mitosis.
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What is a cistron?
Cistron is a segment of DNA that codes for a certain polypeptide or protein.
Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral DNA. How is it possible?
Retroviruses convert their RNA into DNA by the method of reverse transcription, thus it is possible that the DNA of the infected host possesses DNA even when retroviruses do not have their own DNA.
Why do children cured by enzyme-replacement therapy for adenosine deaminase deficiency need periodic treatment?
Children cured by enzyme-replacement therapy for adenosine deaminase deficiency need periodic treatment because these cells are not immortal.
List two advantages of the use of unleaded petrol in automobiles as fuel.
Following are the two advantages of using unleaded petrol as fuel in automobiles:
i. Unleaded petrol does not have lead compounds therefore does not inactivate the catalytic converter.
ii. It does not emit harmful compounds, thus causes less pollution and helps in preventing health diseases like bronchitis, asthma and lung diseases.Sponsor Area
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