Given below are two statements: Statement I: Fungi are important degraders of polymers and are used in the composting and biodegradation of toxic…
Given below are two statements:Statement I: Fungi are important degraders of polymers and are used in the composting and biodegradation of toxic organic substances.Statement II: Fungi are able to selectively excrete toxins present in these polymers.In the light of the above statements, choose the correct answer from the options given below:
Select an option to attempt
Correct Answer: Option C
Explanation
Fungi as polymer degraders — Statement II is false:Statement I: 'Fungi are important degraders of polymers and are used in composting and biodegradation of toxic organic substances.' — TRUE• White-rot fungi (Phanerochaete chrysosporium): degrade lignin via lignin peroxidase, manganese peroxidase, laccase.• Brown-rot fungi: degrade cellulose and hemicellulose.• Fungi produce extracellular oxidases and hydrolases to break down complex polymers.• Used in bioremediation of PAHs, chlorinated compounds, dyes.Statement II: 'Fungi selectively excrete toxins present in polymers.' — FALSE• Fungi do NOT selectively identify and excrete pre-formed toxins from polymers.• What fungi DO: produce extracellular enzymes that enzymatically cleave the polymer backbone.• The resulting degradation products may be less toxic than the parent compound.• Fungi do not have a toxin-extrusion mechanism specifically for polymer-bound toxins.Answer: Statement I is true (fungi are excellent polymer degraders); Statement II is false (they degrade polymers enzymatically, not selectively excrete toxins).