AP BIOLOGY

Detailed explanation-1: -The bacterial enzyme called methyltransferase methylates its own DNA with methyl groups (-CH3) in a process called DNA Methylation. This process allows the bacteria to recognize its own DNA and destroy any foreign DNA ( unmethylated viral DNA) with the help of restriction enzyme.

Detailed explanation-2: -Restriction enzymes are found in bacteria. Bacteria use restriction enzymes to kill viruses – the enzymes attack the viral DNA and break it into useless fragments.

Detailed explanation-3: -restriction enzyme, also called restriction endonuclease, a protein produced by bacteria that cleaves DNA at specific sites along the molecule. In the bacterial cell, restriction enzymes cleave foreign DNA, thus eliminating infecting organisms.

Detailed explanation-4: -Definition. A restriction enzyme is a protein isolated from bacteria that cleaves DNA sequences at sequence-specific sites, producing DNA fragments with a known sequence at each end. The use of restriction enzymes is critical to certain laboratory methods, including recombinant DNA technology and genetic engineering.

Detailed explanation-5: -Restriction enzymes are a group of proteins that bacteria produce to cut up the DNA of invading viruses. Electron micrograph of Escherichia coli, close-up. Such bacteria are an important source for restriction enzymes.