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

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Answer

C

Explanation

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