• They can degrade harmful proteins
• They can join DNA fragments
• They can cut DNA at specific base sequences
• They can cut DNA at variable sites

• cleave DNA at highly specific recognition sequences
• are inserted into bacteria by bacteriophages
• are made only by eukaryotic cells
• cut at random sites.

• Viruses 
• Chromosomes
• Bacteria 
• Chloroplasts

64. “Molecular scissors” used in genetic engineering is :

• DNA polymerase
• DNA ligase
• Restriction endonuclease
• Helicase

• Nirenberg
• Mendel
• Morgan 
• Khorana

• RNA→DNA→ Protein
• Protein→RNA→DNA
• DNA→RNA→Protein
• RNA→Protein→DNA

• Plastic surgery
• Addition or removal of genes
• Study of extranuclear genes
• All the above

Can you recall meiosis and indicate at what stage a recombinant DNA is made?

Can you think and answer how a reporter enzyme can be used to monitor transformation of host cells by foreign DNA in addition to a selectable marker?

Explain with the help of a suitable example the naming of a restriction endonuclease.