1
Question
Assertion :A bacterial cell with no restriction enzymes will be easily infected and lysed by bacteriophages. Reason: Restriction enzymes catalyse synthesis of protective coat around bacterial cell that prevents bacteriophage attack.
Assertion :A bacterial cell with no restriction enzymes will be easily infected and lysed by bacteriophages. Reason: Restriction enzymes catalyse synthesis of protective coat around bacterial cell that prevents bacteriophage attack.
Open in App
Solution
The correct option is C Assertion is correct but Reason is incorrect
Restriction enzymes were named due to the phenomenon of host restriction of bacterial phages. Restriction enzymes produced in a bacterial cell, recognise 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.So, the correct answer is 'Assertion is correct but Reason is incorrect'.
Restriction enzymes were named due to the phenomenon of host restriction of bacterial phages. Restriction enzymes produced in a bacterial cell, recognise 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.
So, the correct answer is 'Assertion is correct but Reason is incorrect'.
Suggest Corrections
0
Similar questions