Which enzyme breaks down starch into sugars? MCQ with Answer and Explanation

Explanation:
CO₂ has sp hybridized carbon, forming two double bonds with oxygen in a linear arrangement (O=C=O) with bond angle 180°. H₂O is bent (angular, 104.5°), NH₃ is trigonal pyramidal (107°), CH₄ is tetrahedral (109.5°). Molecular shape is determined by VSEPR theory: CO₂ has 2 bond pairs, 0 lone pairs → linear.

Explanation:
H₂O₂ decomposes when exposed to light (photochemical decomposition): 2H₂O₂ → 2H₂O + O₂. Light provides energy to break the O–O bond. To prevent decomposition, it is stored in amber or opaque bottles, often with stabilizers like urea or phosphoric acid. Also, traces of heavy metal ions catalyze decomposition. H₂O₂ is a strong oxidizing agent and bleaching agent.

Explanation:
Methanol (wood alcohol) is highly toxic. When ingested, it is metabolized by the enzyme alcohol dehydrogenase into formaldehyde and then formic acid. Formic acid interferes with mitochondrial function, leading to metabolic acidosis, optic nerve damage, and blindness. Both statements are correct and R explains A.