Non-boiled bean seeds show active enzyme function in starch digestion experiment

Steps:

• Non-boiled seeds retain living enzymes like amylase, unlike boiled ones where heat denatures proteins.
• In the presence of starch and iodine, active amylase breaks down starch into sugars.
• Iodine fails to produce a blue-black color with digested starch, explaining the lack of reaction.
• This demonstrates enzyme activity in viable seeds.

Why D is correct:

• D explains the absence of starch-iodine reaction due to enzymatic digestion, per the biological definition of amylase as a starch-hydrolyzing enzyme.

Why the others are wrong:

• A: Iodine absorption does not prevent color change; it binds to intact starch.
• B: Acid presence does not affect iodine-starch test specificity.
• C: While true, amylase alone does not fully account for the result without context of starch breakdown.

Not enough information on exact results or full choice D text to confirm.

Final answer: D