Class 12th Biology 2011 Set1 Delhi Board Paper Solution
Question 9
How do histones acquire positive charge?
Answer
Because DNA is negatively charged molecule, the fine structure of DNA wrapped over histones is termed as nucleosome. Wrapping of DNA on histone helps the long chain of DNA to get accommodated in a small space.
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Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
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(c) toxin is inactive:
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