Assertion: A bacterial cell with no restriction enzymes will be easily infected and lysed by bacteriophages.
Reason: Restriciton enymes catalyse synthesis of protective coat around bacterial cell that prevents bacteriophage attack.

Both Assertion (A) and Reason are false (F ).

Restriction enzymes were named due to the phenomenon of host restriction of bacterial phages. Restriction enzymes produced in a bacterial cell, recognize and cleave foreign DNA introduced (such as from bacteriophage) into the cell. Thus, bacterial cell cannot be infected and lysed by bacteriophage and hence a bacterial cell lacking restriction enzymes is easily susceptible to infection of phages. The DNA of the host bacterial cell is protected from its own restriction endonucleases by methylation (usually of A and C) within their recognition sites.