Which of the following is correct about nucleases?
A
It is a large class of enzymes consisting of exonucleases and endonucleases
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
Exonucleases remove nucleotide from only one end of the DNA
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
Endonucleases make specific cuts within the DNA by breaking ionic bonds
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
All of them recognise palindromic nucleotide sequences in the DNA
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A It is a large class of enzymes consisting of exonucleases and endonucleases Nucleases are a large class of enzymes that degrade DNA by breaking phosphodiester bonds between the nucleotides. Based on its site of action on DNA, they are divided into two types:
Exonuclease
It removes nucleotides by breaking the phosphodiester bond
It removes only one nucleotide at a time from either end of a DNA
It is present in both prokaryotes and eukaryotes
Endonucleases
It recognizes palindromic nucleotide sequences within the DNA molecule called recognition site and breaks phosphodiester bond at a particular nucleotide within the restriction site.
It is present in prokaryotes and provides protection against invading bacteriophage DNA