Question

Assertion :'Cry' proteins are named so because they are crystal proteins. Reason: 'Cry' proteins are solubilised in acidic enviornment of insect midgut and then released toxic core fragments after proteolytic action.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is C Assertion is correct but Reason is incorrect

The cry gene of Bacillus thuringiensis produces a protein, which forms crystalline inclusions (i.e., is crystal in bacterial spores. These proteins are named 'cry' proteins due to their crystal nature and care are responsible for the insecticidal activities of the bacterial strains. 'Cry' proteins undergo proteolytic digestion to release core toxic fragments. These toxin bind to receptors in brush border, membrane develop pores, most likely non-specific in nature border, membrane influx of ions and water likely non-specific in nature and cause influx of ions and water into the cells resulting in their swelling and eventually lysis.

'Assertion is correct but Reason is incorrect'.