THE MOLECULAR BASIS OF INHERITANCE
RECOMBINANT DNA
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
through the gene
|
|
|
on either side of the gene
|
|
|
through the gene and on either side of the gene
|
|
|
twice on each side of the gene
|
Detailed explanation-1: -If EcoRI is used to digest both human chromosomal DNA and a plasmid, it will cut the chromosomal DNA over 700, 000 times (3 billion base pairs, cut every 4096 base pairs), but may only cut the plasmid once (5, 000 base pairs, cut every 4096 base pairs).
Detailed explanation-2: -To cut DNA, all restriction enzymes make two incisions, once through each sugar-phosphate backbone (i.e. each strand) of the DNA double helix.
Detailed explanation-3: -Each restriction enzyme recognizes just one or a few restriction sites. When it finds its target sequence, a restriction enzyme will make a double-stranded cut in the DNA molecule.
Detailed explanation-4: -A circular plasmid can be cleaved using restriction enzymes. These restriction enzymes cleave the plasmid at specific sites. On cleaving a circular DNA 3 fragments of DNA will be obtained as there are 3 recognition sites for restriction enzyme.