Question

Choose the correct pair from the following
A. Polymerase- Break the DNA into fragments
B. Nucleases- Separates the two strands of DNA.
C. Exonuclease- Makes cuts at specific positions within DNA
D. Ligases- Join the two DNA molecules

Answer 1

Hint: Deoxyribonucleic acid (DNA) is a molecule made up of two polynucleotide chains that coil around each other to form a double helix and contain genetic instructions for the creation and operation of all living things. DNA structure is made of bases, sugars and phosphate. DNA structure was developed by Watson and Crick models.

Complete answer:
Option A: A polymerase is an enzyme that produces long polymers of nucleic acid chains. By copying a DNA reference strand using base-pairing interactions or RNA by half ladder replication, DNA and RNA polymerase are used to assemble DNA and RNA molecules, respectively.
So, option A is incorrect.
Option B: A nuclease is a nucleic acid enzyme that can cleave the phosphodiester bonds between nucleotides. Nucleases cause single and double stranded breaks in their target molecules in different ways.
So, option B is incorrect.
Option C: Exonucleases are enzymes that cleave nucleotides one by one from the end of a strand of DNA.
So, option C is incorrect.
Option D: Joining enzyme is DNA ligase. Ligase will join two pieces of DNA with matching ends to form a single, unbroken molecule of DNA. Restriction enzymes and DNA ligase are used in DNA cloning to inject genes and other DNA fragments into plasmids.
So, option D is correct.

Hence, Option D is the correct answer.

Note:
A gene is a piece of DNA that holds information and passes it on from generation to generation. Transcription into RNA and then translation into proteins are the first steps of gene expression in DNA. The DNA molecule is a two-stranded spiral that forms a double helix. Each strand is made up of millions of bases, which are chemical building blocks. Adenine, thymine, cytosine, and guanine are the only four groups of bases found in DNA. Permutation and combination in a sequence alter the order of these bases.