An interesting property of restriction enzymes is molecular cutting. Restriction enzymes typically recognise a symmetrical sequence of DNA.

Notice that the top strand is the same as the bottom strand, but reads backward. When the enzyme cuts the strand between G and A, it leaves overhanging chains :

(a) What is this symmetrical sequence of DNA known as?
(b) What is the significance of these overhanging chains?
(c) Name the restriction enzyme that cuts the strand between G and A.

Explanation

(a) Palindromic nucleotide sequence/ Recognition sequence.
(b) DNA fragments from two different molecules which have the same kind of sticky ends or overhanging chains can be joined together (end to end) by DNA ligases.
(c) feaR!.