17. (b) Thymine is not present in
RNA is very much similar as DNA but in case of RNA is single
stranded structure with ribose sugar and in ribose sugar use of
uracil instead of Thymine which is present in deoxyribose sugar
present in DNA. In RNA uracil is present which maintain the
structure but lifespan is very low compared to the thymine.
18. (d) A plasmid is chromosomal eukaryotic
This answer is partially correct because most of the plasmid is
prokaryotic. Because plasmids are double stranded DNA molecules
present in bacteria and bacteria is prokaryotic in nature.
19. (c) –TAACCGG– is
compliment of DNA sequence.
Because DNA always present in double stranded form first strand
is leading strand and other is lagging strand when two differ stand
cross each other make a fragment is known as Okazaki fragment.
Base pairs compliment according to the their size (1 :1) which
is defined by Austrian chemist Erwin Chargaff.
And in modern recombinant DNA technology is known as Chargaff’s